query: where are the walking legs of crustaceans found

pos: Crustacean include two pairs of antennae, the mandibles and maxillae; the thoracic segments bear legs, which may be specialised as pereiopods (walking legs) and maxillipeds (feeding legs). The abdomen bears pleopods, and ends in a telson, which bears the anus, and is often flanked by uropods to form a tail fan. The number and variety of appendages in different crustaceans may be partly responsible for the group's success. Crustacean appendages are typically biramous, meaning they are divided into two parts; this includes the second pair of antennae, but not the first, which is usually uniramous, the exception being in the Class

neg: Aquatic locomotion gliding; the organism floats, using currents where it can, and does not exert any energy into controlling its position or motion. Active swimming, in contrast, involves the expenditure of energy to travel to a desired location. In bilateria, there are many methods of swimming. The arrow worms (chaetognatha) undulate their finned bodies, not unlike fish. Nematodes swim by undulating their fin-less bodies. Some Arthropod groups can swim - including many crustaceans. Most crustaceans, such as shrimp, will usually swim by paddling with special swimming legs (pleopods). Swimming crabs swim with modified walking legs (pereiopods). Daphnia, a crustacean, swims by beating

neg: Gonopod insects, gonopods are appendages of the genital segment that may be used in insemination, or that comprise the egg-laying apparatus. In male decapod crustaceans, gonopods are modified swimming appendages (pleopods). The anterior two pair of pleopods in males are modified for sperm transferring, with differing degree of morphological diversification. In millipedes, gonopods consist of one or two pairs of often highly modified walking legs in mature males, and are primarily found in members of the subgroup Helminthomorpha- containing most orders and the vast majority of species- where they are located on the seventh body segment consisting of leg pairs 8

neg: Astacidea of chelae (claws) on each of the first three pairs of pereiopods (walking legs), the first of which is much larger than the remaining two pairs. The last two pairs of pereiopods are simple (without claws), except in "Thaumastocheles", where the fifth pereiopod may have "a minute pincer". Members of the infraorder Astacidea are found throughout the world – both in the oceans and in fresh water – except for mainland Africa and parts of Asia. Astacidea Astacidea is a group of decapod crustaceans including lobsters, crayfish and their close relatives. The infraorder Astacidea comprises five extant superfamilies, two of

neg: Hexapoda each of which bears a single pair of legs. As is typical of arthropods adapted to life on land, each leg has only a single walking branch composed of five segments, without the gill branches found in some other arthropods and with gill on the abdominal segments of some immature aquatic insects. In most insects the second and third thoracic segments also support wings. It has been suggested that these may be homologous to the gill branches of crustaceans, or they may have developed from extensions of the segments themselves. The abdomen follow epimorphic development, where all segments are already

neg: Cyclida walking legs, in the form of the mouthparts and in other significant ways. There is considerable debate about the placement of cycloids within the Arthropoda. While they are generally considered to be crustaceans of some kind, doubts have been expressed about the homology of cycloids' respiratory structures with those of other crustaceans, and parallels drawn instead with chelicerates. The first description of a cycloid was in the 1836 treatise "Illustrations of the Geology of Yorkshire" by John Phillips, where Phillips described ""Agnostus ? radialis"" among the trilobites, with the text "ribs radiating, with acute puncta; abdomen mucronate". In 1838, Hermann

neg: Tokummia katalepsis 10 cm long and has a two piece carapace on its back. It was a bottom feeder, being able to walk on the sea floor, and to occasionally swim. The animal legs have endites which are small spikes on the legs. It has one pair of antennae. The genus was named after Tokumm Creek which runs through the Marble Canyon where this was found. The species was named after a Greek word for gasping. The discoverers claim that "Tokummia" along with "Branchiocaris", "Canadaspis" and "Odaraia" are very early crustaceans ancestral to the Mandibulata grouping, which includes millipedes, insects and crustaceans.

neg: Coxal gland sex pheromone. Coxal gland The coxal gland is a gland found in some arthropods, for collecting and excreting urine. They are found in all arachnids (with the exception of some Acari), and in other chelicerates, such as horseshoe crabs. The coxal gland is thought to be homologous with the antennal gland of crustaceans. The gland consists of an end sac ("saccule"), a long duct ("labyrinth") and a terminal bladder ("reservoir"). There is generally only one pair (two in some spiders), and they open on the coxae of the walking legs. The coxal secretion of adult female ticks of "Ornithodoros erraticus"

neg: Coxal gland Coxal gland The coxal gland is a gland found in some arthropods, for collecting and excreting urine. They are found in all arachnids (with the exception of some Acari), and in other chelicerates, such as horseshoe crabs. The coxal gland is thought to be homologous with the antennal gland of crustaceans. The gland consists of an end sac ("saccule"), a long duct ("labyrinth") and a terminal bladder ("reservoir"). There is generally only one pair (two in some spiders), and they open on the coxae of the walking legs. The coxal secretion of adult female ticks of "Ornithodoros erraticus" contains a

neg: Sea spider insects or crustaceans. This is in dispute, however, as genetic evidence suggests they may be the sister group to all other living arthropods. Sea spiders have long legs in contrast to a small body size. The number of walking legs is usually eight (four pairs), but species with five and six pairs exist. Because of their small size and thin body and legs, no respiratory system is necessary, with gases moving by diffusion. A proboscis allows them to suck nutrients from soft-bodied invertebrates, and their digestive tract has diverticula extending into the legs. Certain Pycnogonids are so small that each

neg: Oregonia gracilis "Oregonia gracilis" have three body segments: head, thorax and abdomen. Like many crustaceans, the head and thorax combine into a cephalothorax and are completely covered in a continuous exoskeleton called a carapace. The carapace is heart shaped, a brown, tan or grey color and 5 cm in length with five long thin walking legs (pereopods) attached to it. The first three pereopods are called maxipelleds and are used for feeding. Another pair of the legs have pincers attached and are called chelipeds. The chelipeds are used for feeding defense, and to decorate their bodies. The chelipeds, are longer than the

neg: Pain in crustaceans "Caenorhabditis elegans", "Drosophila melanogaster" and larval "Manduca sexta". The bodies of crustaceans are segmented; there is one ganglion (cluster of nerve cells) per segment. Each ganglion receives sensory and movement information via nerves coming from the muscles, body wall, and appendages such as walking legs, swimmerets and mouthparts. The ganglia show great functional autonomy; information received by the ganglion is processed by the same ganglion, enabling a faster response than if the message had to travel all the way up the animal's body to the brain and then back. Information can be exchanged between ganglia enabling the animal to perform

neg: Nephrops norvegicus capture with their chelipeds and walking legs, and food is conveyed to the mouth using the anterior walking legs, assisted by the maxillipeds. There is evidence that "Nephrops norvegicus" is a major eater of jellyfish. "Nephrops norvegicus" is the host to a number of parasites and symbionts. A number of sessile organisms attach to the exoskeleton of "N. norvegicus", including the barnacle "Balanus crenatus" and the foraminiferan "Cyclogyra", but overall "Nephrops" suffers fewer infestations of such epibionts than other decapod crustaceans do. In December 1995, the commensal "Symbion pandora" was discovered attached to the mouthparts of "Nephrops norvegicus", and was

neg: Neumania papillator the aquatic vegetation, they hunt copepods (small crustaceans) which pass by in the water column. When hunting "N. papillator" adopts a characteristic stance termed the 'net stance' - their first four legs are held out into the water column, with their four hind legs resting on aquatic vegetation. This allows them to detect vibrational stimuli produced by swimming prey and thus orient towards and then clutch at the prey. During courtship, males actively search (swimming/walking) for females - if a male finds a female, he slowly circles around her whilst trembling his first and second leg near the female. Males

neg: Gonopod Gonopod Gonopods are specialized appendages of various arthropods used in reproduction or egg-laying. In males, they facilitate the transfer of sperm from male to female during mating, and thus are a type of intromittent organ. In crustaceans and millipedes, gonopods are modified walking or swimming legs. Gonopods may be highly decorated with elaborate structures which may play roles in sperm competition, and can be used to differentiate and identify closely related species. Gonopods generally occur in one or more pairs, as opposed to the single (un-paired) reproductive organs such as the aedeagus of insects or the penis of harvestmen. In

neg: Seta have mechano- and chemosensory setae. Setae are especially present on the mouthparts of crustaceans and can also be found on grooming limbs. In some cases, setae are modified into scale like structures. Setae on the legs of krill and other small crustaceans help them to gather phytoplankton. It captures them and allows them to be eaten. Setae on the integument of insects are unicellular, meaning that each is formed from a single epidermal cell of a type called a trichogen, literally meaning "bristle generator". They are at first hollow and in most forms remain hollow after they have hardened. They

neg: Bas-Lag errands. Many races of Bas-Lag are only briefly mentioned in passing. The Llorgiss are a tri-faceted, barrel-shaped race. The Gessin are said to be large, and might wear armor. Menfish are some sort of newt/merman aquatic race. A reference is made to "“crustaceans walking on two legs and cowled like monks, figures with too many eyes.” A race of waist-high insect people were mentioned in Iron Council. The races "Vu-murt" and "Corokanth" were named, but the races were not described. The Remade are usually, but not always, the victims of the criminal justice system. Rather than imprisoning criminals, the city

neg: Shrimp crabs and lobsters. These species have small abdominal appendages, but robust legs well adapted for walking. The Natantia was thought to be paraphyletic, that is, it was thought that originally all decapods were like shrimp. However, classifications are now based on clades, and the paraphyletic suborder Natantia has been discontinued. "On this basis, taxonomic classifications now divide the order Decapoda into the two suborders: Dendrobranchiata for the largest shrimp clade, and Pleocyemata for all other decapods. The Pleocyemata are in turn divided into half a dozen infra-orders" Other decapod crustaceans also called shrimp, are the ghost or mud shrimp belonging

neg: Octopus to the suggestion that the two rearmost appendages may be more accurately termed "legs" rather than "arms". Some species of octopus can crawl out of the water briefly, which they may do between tide pools while hunting crustaceans or gastropods or to escape predators. "Stilt walking" is used by the veined octopus when carrying stacked coconut shells. The octopus carries the shells underneath it with two arms, and progresses with an ungainly gait supported by its remaining arms held rigid. Octopuses are highly intelligent; the extent of their intelligence and learning capability are not well defined. Maze and problem-solving experiments

neg: Greater painted-snipe that it can retreat to cover if disturbed. When flushed, flies like a rail with legs dangling. Bobs hindquarters on landing and sometimes when walking. Probes for food in the mud. The female initiates courtship and may mate with more than one male. The male incubates the eggs. They feed on insects, crustaceans, molluscs and seeds. The females court the males, are polyandrous with males incubating and raising the young as predicted by parental investment theory. Chicks are buff coloured and have black stripes running along their length. Immature birds resemble the male but lack the broken dark band across

neg: Acutiramus modern crustaceans, with well-developed teeth on the claws, than to the chelicerae of other eurypterid groups. Another feature distinguishing the group from other eurypterid groups were their flattened and expanded telsons, likely used as rudders when swimming. Their walking legs were small and slender, without spines, and they were likely not capable of walking on land. "A. bohemicus" was once estimated to have reached lengths of 2.3 to 2.5 metres (7.5 to 8.2 ft) based on the largest known chelicerae and coxae. This would have made it the largest known arthropod, but recent estimates have revised the upper size limits

neg: Facultative bipedalism are examples of this: their movement through trees makes quadrupedal walking difficult, resulting in bipedal walking and galloping, respectively. Arboreal adaptations making bipedalism advantageous are supported by research that shows that hip and thigh muscles involved in the bipedal walking often most resemble those used in climbing. Facultative bipedalism A facultative biped is a animal that is capable of walking or running on two legs (bipedal), as a response to exceptional circumstances (facultative), while normally walking or running on four limbs or more. In contrast, obligate bipedalism is where walking or running on two legs is the primary method of

neg: Arthropod leg the tarsus. The claws of the scorpion are not truly legs, but are pedipalps, a different kind of appendage that is also found in spiders and is specialised for predation and mating. In "Limulus", there are no metatarsi or pretarsi, leaving six segments per leg. The legs of crustaceans are divided primitively into seven segments, which do not follow the naming system used in the other groups. They are: coxa, basis, ischium, merus, carpus, propodus, and dactylus. In some groups, some of the limb segments may be fused together. The claw of a lobster or crab is formed by the

neg: Cyclograpsus lavauxi walking legs close and side-by-side. When in a raised position they place their body at a 45 degree angle with their back part still laying on the ground with their pincers resting still either flat or poised at the midway mark. Their final position is the tiptoe position with their body angled and lifted off the ground and in the air, pincers still folded but held off the ground with their walking legs fully extended. Moreover, another fascinating thing that has been found about the "C.lavauxi" is that they are usually found under stones, with their hind legs grasping stones

neg: Walking vehicle Walking vehicle A walking vehicle is a vehicle that moves on legs rather than wheels or tracks. Walking vehicles have been constructed with anywhere from one to more than eight legs. They are classified according to the number of legs with common configurations being one leg (pogo stick or "hopper"), two legs (biped), four legs (quadruped), and six legs (hexapod). There are a few prototypes of walking vehicles. Currently almost all of these are experimental or proof of concept, and as such may never see mass production. While the mobility of walking vehicles is arguably higher than that of wheeled

neg: Macrobrachium rosenbergii until their shells have hardened; OCs and SMs show no such behaviour. In mating, the male deposits spermatophores on the underside of the female's thorax, between the walking legs. The female then extrudes eggs, which pass through the spermatophores. The female carries the fertilised eggs with her until they hatch; the time may vary, but is generally less than three weeks. Females lay 10,000–50,000 eggs up to five times per year. From these eggs hatch zoeae, the first larval stage of crustaceans. They go through several larval stages before metamorphosing into postlarvae, at which stage they are long and resemble

neg: Restless legs syndrome iron deficiency, varicose veins, and thyroid problems. Stretching the leg muscles can bring temporary relief. Walking and moving the legs, as the name "restless legs" implies, brings temporary relief. In fact, those with RLS often have an almost uncontrollable need to walk and therefore relieve the symptoms while they are moving. Unfortunately, the symptoms usually return immediately after the moving and walking ceases. A vibratory counter-stimulation device has been found to help some people with primary RLS to improve their sleep. Non-drug treatments include leg massages, hot baths, heating pads or ice packs applied to the legs, good sleep habits

neg: Marpissa pikei legs and carapace orange, the female has a duller coloration, with the abdomen pale cream-colored, speckled with black. These spiders are very hard to find when not moving. Once they do move, they do so exceedingly quick and jerky. The enlarged first pair of legs is not used in walking, but are extended in front. When males spot a female, they approach it with their front legs extended and waving, prior to mating. They are usually found on low grasses. Kaston (1981) reports it as readily swept from tall grasses, especially along seashores. In Kansas, adults are found from May

neg: Oregonia gracilis walking legs in males and shorter than the walking legs in females. Two long stalked compound eyes protrude from the cephalothorax. Behind each eye is a large and curved postorbital spine. Using fine hooked setae found on the carapace, the crab liberally decorates itself with algae, sponges, bryozoans and hydroids. Its shell covered in sessile organisms makes the crab camouflaged to its environment. Juveniles and adult females decorate heavily whereas adult males are sparse in their decoration. "O. gracilis" live in the intertidal zone up to 436 meters deep. The can be found in the Bering Sea, the North Pacific

neg: Pain in crustaceans is fully blocked by naloxone. Crustaceans have a functional opioid system which includes the presence of opioid receptors similar to those of mammals. Delta- and Kappa-opioid receptors have been described in crustaceans. RT-PCR research on the American lobster ("Homarus americanus") has revealed the presence of a Mu-opioid receptor transcript in neural and immune tissues, which exhibits a 100% sequence identity with its human counterpart. In the American lobster, endogenous morphine is found in the haemolymph and ventral nerve cord. In lobsters which have had a pereiopod (walking leg) cut off or been injected with the irritant lipopolysaccharide, the endogenous morphine

neg: Panulirus pascuensis of the antennae. There are no claws on the first four pairs of walking legs. The colour of this spiny lobster is dark greenish purple with pale transverse bands on the posterior edge of the abdominal segments. The base of the tail fan has pale spots and the antennae are a uniform colour. The walking legs have slender longitudinal pale stripes. "Panulirus pascuensis" is native to the south eastern Pacific Ocean, round the coasts of Easter Island and Pitcairn Island at depths of up to . It is also reported from the Austral Islands in French Polynesia. It is found

neg: Hexapus Hexapus Hexapus is a genus of crabs in the family Hexapodidae. It contains only three extant species found in the Indo-West Pacific. They inhabit the intertidal and subtidal areas of shorelines. Like other members of the family, these crabs are easily recognizable due to the complete absence of the last pair of walking legs (pereiopods). They thus only have six walking legs (excluding the claws), unlike the usual eight. Their carapace is subquadrate, wider than it is long, with a rounded anterior. The following are the species classified under "Hexapus". "Hexapus estuarinus" is now regarded as a junior synonym of

neg: Hexapus "Hexapus sexpes". In addition, the following the species has been transferred to other genera: Hexapus Hexapus is a genus of crabs in the family Hexapodidae. It contains only three extant species found in the Indo-West Pacific. They inhabit the intertidal and subtidal areas of shorelines. Like other members of the family, these crabs are easily recognizable due to the complete absence of the last pair of walking legs (pereiopods). They thus only have six walking legs (excluding the claws), unlike the usual eight. Their carapace is subquadrate, wider than it is long, with a rounded anterior. The following are the

neg: Arthropod leg have been lost or become vestigial through evolutionary adaptation, adult insects have six legs, one pair attached to each of the three segments of the thorax. They do also have paired appendages on some other segments, in particular, mouthparts, Antennae and cerci, all of which are suspected to be derived from paired legs on each segment of some common ancestor. Some larval insects do however have extra walking legs on their abdominal segments; these extra legs are called prolegs. They are found most frequently on the larvae of moths and sawflies. Prolegs do not have the same structure as modern

neg: Arthropod mouthparts a pair of "poison claws", or forcipules. These, like the maxillipeds of crustaceans, are modified legs and not true mouthparts. The forcipules arise from the first body segment, curving forward and to the midline. The tip is a pointed fang, which has an opening from a venom gland. The forcipules are used to capture and envenomate prey. Crustaceans comprise a number of classes, with various feeding modes supported by a range of adaptions to the mouthparts. In general, however, crustaceans possess paired mandibles with opposing biting and grinding surfaces. The mandibles are followed by paired first and second maxillae. Both

neg: Ocypode though they are capable of gradually changing body coloration to match their environment and the time of day. The claw-bearing legs (chelipeds) of both sexes are unequal in size, with one much larger than the other. The palm of the claws also possess stridulating (sound-producing) ridges which they use for communication. These ridges are also important morphological characters useful for identifying species. The chelipeds are shorter than the walking legs. The last pair of walking legs (pereiopods) is also usually shorter and thinner than the other pairs of walking legs. A cavity, with edges fringed by long setae are also

neg: Hyloidea placing frogs into this family when the relationships to others are unknown. Therefore, Hyloidea has the highest species diversity. Hyloidea are all tailless, have shortened bodies, large mouths and muscular hind legs. Most anurans in the superfamily have a lateral‐bender which is a type of pelvis morphology found in walking, hopping and burrowing frogs. Some species that appear later in the taxon have a sagittal‐hinge pelvis found in aquatic frogs as well as walking, hopping and burrowing frogs and some have a fore–aft slider pelvis found in terrestrial frogs. The morphological characteristics between anurans are very similar, therefore DNA testing

neg: Carcinosomatidae Carcinosomatidae Carcinosomatidae is a family of extinct arthropods in the class Eurypterida. These eurypterids are found from the Silurian to the Devonian periods. The family contains four genera; "Carcinosoma", "Eocarcinosoma", "Eusarcana" and "Rhinocarcinosoma". Carcinosomatids were characterized by small to large exoskeletons with scattered minute tubercules or raised tongue-shaped scales. The prosoma (head) was subtriangular, with small compound eyes at the front. The chelicerae (claws in front of the mouth) were small. The walking legs were covered with long spines, and the second pair of walking legs was the longest. The preabdomen, the front portion of the body, was broad and

neg: Freshwater prawn farming Antarctica. Giant river prawns live in turbid freshwater, but their larval stages require brackish water to survive. Males can reach a body size of 32 cm; females grow to 25 cm. In mating, the male deposits spermatophores on the underside of the female's thorax, between the walking legs. The female then extrudes eggs, which pass through the spermatophores. The female carries the fertilized eggs with her until they hatch; the time may vary, but is generally less than three weeks. A large female may lay up to 100,000 eggs. From these eggs hatch zoeae, the first larval stage of crustaceans.

neg: Tennessee Walking Horse and hip are long and sloping, with a short back and strong coupling. The hindquarters are of "moderate thickness and depth", well-muscled, and it is acceptable for the hind legs to be slightly over-angulated, cow-hocked or sickle-hocked. They are found in all solid colors, and several pinto patterns. Common colors such as bay, black and chestnut are found, as are colors caused by dilution genes such as the dun, champagne, cream and silver dapple genes. Pinto patterns include overo, sabino and tobiano. The Tennessee Walking Horse has a reputation for having a calm disposition and a naturally smooth riding gait.

neg: Hypothalassia acerba two species in the genus "Hypothalassia", and "H. acerba" is not the same "champagne crab" as the other "Hypothalassia" species, "H. armata", which is found in Japanese waters. The species has well-defined groves on a hexagonal carapace, with a smooth dorsal surface and a spiny anterior surface. Carapace width is 150 mm. Their branchial openings are partially covered by maxillipeds, and have asymmetrical chelipeds with stiff, brown-black spines of various sizes on their walking legs. The frontal region is beige-cream and covered in many short setae. Walking legs have a dactylus of 3.7–4.3 times as long as wide. Although life

neg: Legs-forward (hieroglyph) or mines. Though not appearing in the Rosetta Stone, (or the lost beginning half used from the "Nubayrah Stele"), the twin concept with the "Walking Legs-returning" shows how either can be interchanged. And besides Ptolemy V whose name uses the returning walking feet as Ptolemy, "illustrious"-("pr (hieroglyph)-r-feet"=Epiphany), "eucharistos", one good example is shown from line 18, (Nubayrah Stele): The going in-and-coming out ideas are complex and interchangeable, as can be shown by the word "depart": it uses the Walking Legs-returning hieroglyph. Legs-forward (hieroglyph) The Walking Legs-forward is an Ancient Egyptian language hieroglyph of the concept of action, part of "going

neg: Arthropod leg Ephemeroptera are adapted to scuttling beneath underwater stones and the like, whereas the adults have more gracile legs that are less of a burden during flight. Again, the young of the Coccoidea are called "crawlers" and they crawl around looking for a good place to feed, where they settle down and stay for life. Their later instars have no functional legs in most species. Among the Apterygota the legs of immature specimens are in effect smaller versions of the adult legs. Arthropod leg The arthropod leg is a form of jointed appendage of arthropods, usually used for walking. Many of

neg: Mountain caracara Mountain Caracara's head and throat remain feathered (unlike some vultures), and only its lores are kept naked. Its legs are yellow and the males and females look similar, while the juveniles are brown. Mountain Caracaras are endemic to South America and are found throughout several countries, including Bolivia, Chile, Peru and Argentina. They prefer unforested regions where they can perch on power poles or fence posts to overlook a large area. They are usually grouped near cities and along highways. A highly opportunistic bird commonly seen walking on the ground, it feeds on both carrion and virtually any small animal

neg: Mithrax spinosissimus reddish-brown carapace and walking legs. The claws are smooth, purplish gray, with a single row of nodules along outer edge and blunt claw tips. The legs are covered with numerous short spines and nodules. It is the largest species of Caribbean reef crab. "M. spinosissumus" is common throughout the Caribbean, Florida and Bahamas; it can reach a length of up to 7 inches and has been found as deep as 130 feet. Often found in caves or beneath reef overhangs. It was made the type species of a separate genus Maguimithrax by Klompmaker "et al." (2015). Mithrax spinosissimus Mithrax spinosissimus,

neg: Agnostida the order Agnostida within the class Trilobita remains uncertain, and there has been continuing debate whether they are trilobites or a stem group. The challenge to the status has focused on Agnostina partly due to the juveniles of one genus have been found with legs differing dramatically from those of adult trilobites, suggesting they are not members of the lamellipedian clade, of which trilobites are a part. Instead, the limbs of agnostids closely resemble those of stem group crustaceans, although they lack the proximal endite, which defines that group. They are likely the sister taxon to the crustacean stem lineage,

neg: Amphipoda lasting damage. Amphipoda Amphipoda is an order of malacostracan crustaceans with no carapace and generally with laterally compressed bodies. Amphipods range in size from and are mostly detritivores or scavengers. There are more than 9,900 amphipod species so far described. They are mostly marine animals, but are found in almost all aquatic environments. Some 1,900 species live in fresh water, and the order also includes terrestrial animals and sandhoppers such as "Talitrus saltator". The name "Amphipoda" comes, via the New Latin "", from the Greek roots ("different") and ("foot"), in reference to two kinds of legs that amphipods possess. This

neg: Amphipoda Amphipoda Amphipoda is an order of malacostracan crustaceans with no carapace and generally with laterally compressed bodies. Amphipods range in size from and are mostly detritivores or scavengers. There are more than 9,900 amphipod species so far described. They are mostly marine animals, but are found in almost all aquatic environments. Some 1,900 species live in fresh water, and the order also includes terrestrial animals and sandhoppers such as "Talitrus saltator". The name "Amphipoda" comes, via the New Latin "", from the Greek roots ("different") and ("foot"), in reference to two kinds of legs that amphipods possess. This contrasts with

neg: Species of The Saga of Seven Suns are unintelligent and are about the size of a rabbit, covered in fur and have long legs and antenna like a cricket. They are only found on Corribus. Furry crickets are portrayed as being readily tamed and affectionate despite appearing to be the primary prey animal for the known local predators. They are edible by humans even though they apparently don't taste very good. Lowriders are carnivorous, crustaceans from the klikiss world of Corribus. They are described as having five eyes, a flattened spherical centre body and clockwork jaws. They live on furry cricket and flying creatures. They are noted

neg: Horseshoe crab swimming, and moving food into the mouth, each with a claw at the tip, except for the last pair. Behind its legs, the horseshoe crab has book gills, which exchange respiratory gases, and are also occasionally used for swimming. As in other arthropods, a true endoskeleton is absent, but the body does have an endoskeletal structure made up of cartilaginous plates that support the book gills. They are more often found on the ocean floor searching for worms and molluscs, which are their main food. They may also feed on crustaceans and even small fish. Females are about 20–30% larger

neg: Eusarcana between 2004 and 2007. The features of "Eusarcana" indicate that its lifestyle was completely different from many other swimming eurypterids, such as "Eurypterus". When walking, "Eusarcana" would likely have lifted the eye-bearing frontal part of its head above the ground, as indicated by the larger size of the forward walking legs and the placement of the eyes. In contrast, "Eurypterus" would have kept its head, shovel-shaped and broad, down to the ground while walking. Furthermore, the walking legs of "Eusarcana" are more powerful than those of "Eurypterus" in general. The legs decrease in strength the further back they are, indicating

neg: Lysmata amboinensis wider scarlet red bands. There are several symmetrical white spots on the red tail. The most anterior antennae fork into two making the shrimp appear to have three pairs of antennae. As with all decapods there are 10 pairs of walking legs, with the most anterior pair having forceps (pincers). Anterior to the walking legs are a pair of white maxillipeds used for feeding. Underneath the thorax behind the walking legs are paired pleopods (swimmerets) used for swimming and brooding eggs. "L. amboinesis" have a pair of stalked eyes though experiments suggest they have coarse vision and are colour blind;

neg: Panulirus cygnus also used to refer to this species, along with many other crustaceans. Panulirus cygnus Panulirus cygnus is a species of spiny lobster (family Palinuridae), found off the west coast of Australia. "Panulirus cygnus" is the basis of Australia's most valuable fishery, making up 20% of value of Australia's total fishing industry, and is identified as the western rock lobster. The species has five pairs of legs that are used to move across the ocean floor, the fifth set possessing claws in the female, and six smaller pairs are located at the mouth. The eyes are located at the ends of

neg: Cephalocarida side, used in locomotion, a forked inner branch and two outer lobes - referred to as the "pseudoepipod" and the "exopod". The structural and functional similarity between the maxillae and the legs may be a sign of primitive organization; the maxillae are not specialized, as they are in other crustaceans. The thorax consists of 10 segments, and the abdomen bears a telson but no other appendages. Cephalocaridans are found from the intertidal zone down to a depth of , in all kinds of sediments. Cephalocaridans feed on marine detritus. To bring in food particles, they generate currents with the thoracic

neg: Terrestrial locomotion Knuckle-walking allows the foot (hand) to specialise for food gathering and/or climbing, as with the great apes and the extinct chalicotheres, or for swimming, as with the platypus. In animals where feet have evolved into functional hands, hand walking is also possible. Among terrestrial invertebrates there are a number of leg forms. The arthropod legs are jointed and supported by hard external armor, with the muscles attached to the internal surface of this exoskeleton. The other group of legged terrestrial invertebrates, the velvet worms, have soft stumpy legs supported by a hydrostatic skeleton. The prolegs that some caterpillars have in

neg: Lethocerus americanus Lethocerus americanus Lethocerus americanus is a giant water bug in the family Belostomatidae, native to southern Canada and the United States (north of 35°N; other "Lethocerus" species are found southwards). It typically has a length around . It was originally classified as a species in genus "Belostoma". Commonly found in ponds, marshes, and on the edges of lakes and slow-moving streams, creeks, adults and larvae feed on other insects, small crustaceans (crabs/crayfish), tadpoles, snails, and small fish. The adult swims with the aid of its hind legs. A pair of front fore limbs is used for capturing and latching onto

neg: Earless monitor lizard found to bite often, resulting in wounds that are relatively deep (compared to those from similar-sized lizards) and can bleed extensively. Recent studies have found both venom glands, and toxic compounds in the bite of this species. They typically feed on earthworms, crustaceans and fish. In captivity, they will eat fish (both whole and pierces), earthworms, squid, shrimp, tadpoles, yolk from green sea turtle eggs, pieces of pig and chicken liver, baby mice and mussels, but refuse to take bird eggs and legs of frog. In captivity adults typically eat once or twice per week, but sometimes enter longer periods

neg: Stomotheca not end in pad-like structures and are reduced in many groups. Where they are fully developed, they probably aid in food intake. Similar lobular structures are sometimes found on the two latter pairs of legs as well, but their function is unknown. The "labium", when present, is a flattened plate derived from the somite of the first walking leg. While large in many Eupnoi and Dyspnoi, it is small in most Laniatores and absent in Cyphophthalmi. The term "stomotheca" is derived from Ancient Greek "stoma" "mouth" and "theca" "case, box". Stomotheca Stomotheca is the term applied to the feeding apparatus

neg: Notomithrax ursus with small bristles. Some of the bristles along the carapace are short and hooked while others are long and straight. The abdomen has seven segments in both sexes with the male abdomen being more narrowwith the segments being broader than longer. The legs are longest in the front and get progressively shorter towards the back. It has three pairs of walking legs, a pair of swimming legs in the back, and a pair of claws at the front called chelipeds. The walking legs are long and slender with the back of the legs covered in a longitudinal row of short

neg: Megalograptidae mouth) are small and short. The first and third pairs of walking legs are short, with diverging or closely spaced spines. The second pair of walking legs is enormously developed, with long paired spines. The fourth pair of walking legs are nearly spineless. The preabdomen, the front portion of the body, is narrow with axial furrows, while the postabdomen is moderately narrow with broad, flat and curved appendages on the last body segment. The telson is short and lanceolate. The Megalograptidae are thought to be relatively primitive (between the genus "Onychopterella" and the Eurypteroidea) because they lack the synapomorphy of

neg: Macrobrachium rosenbergii The rostrum is very prominent and contains 11 to 14 dorsal teeth and 8 to 11 ventral teeth. The first pair of walking legs (pereiopods) are elongated and very thin, ending in delicate claws (chelipeds) which are used as feeding appendages. The second pair of walking legs are much larger and powerful, especially in males. The movable claws of the second pair of walking legs are distinctively covered in dense bristles (setae) that give it a velvety appearance. The color of the claws in males varies according to their social dominance. Females can be distinguished from males by their wider

neg: Phrynus longipes Phrynus longipes Phrynus longipes is a species of Amblypygid found in the Caribbean. They are nocturnal predators that hide during the day in small retreats, and are sit-and-wait predators at night. "P. longipes" can be found in subtropical and tropical forests, and caves within their range. The body of "P. longipes" can measure up to long, but its front legs can reach long. Like other Amblypygi, "Phrynus longipes" has eight pairs of legs with six used for walking and the first employed as sensory organs for detecting prey and navigating their environment. Its cephalothorax is wider than it is long

neg: Gibbonsia elegans on their diet. Color changes are also dependent on season. During the winter, more red Gibbonsia were found when red algae were dominant. In the spring and summer, green and brown morphs are prevalent. Male and female "Gibbonsia" are commonly found in different vertical distributions. Females are more frequently found in shallow habitats whereas males are found more commonly as the depth increases. They primarily feed on epiphytic crustaceans. These crustaceans are found on the same plants that "Gibbonsia" live on, including brown and red algae. The epiphytic crustaceans also match the color of their plant habitat. Their diet consists

neg: Pacific viperfish from a single ovigerous female infecting a Pacific viperfish collected from the deep-waters of Suruga Bay, Japan. According to the authors, the new genus had the most plesiomorphic states in the first to fourth legs of pennellid copepods. Pacific viperfish The Pacific viperfish, "Chauliodus macouni", is a predatory fish that lives in the abyssal depths of the deep sea. In daytime it can be found from 200–5000 m below the ocean surface. At night it swims up into shallower depths of less than 200m where food is more plentiful. Pacific viperfish will mostly eat crustaceans and small fish. They typically

neg: Appendage become "uniramous", as in insects and centipedes, where each appendage comprises a single series of segments, or it may be "biramous", as in many crustaceans, where each appendage branches into two sections. "Triramous" (branching into three) appendages are also possible. All arthropod appendages are variations of the same basic structure ("homologous"), and which structure is produced is controlled by "homeobox" genes. Changes to these genes have allowed scientists to produce animals (chiefly "Drosophila melanogaster") with modified appendages, such as legs instead of antennae. Appendage In invertebrate biology, an appendage (or outgrowth) is an external body part, or natural prolongation, that

neg: Ocypode found in between the bases of the second and third walking legs. "Ocypode" ghost crabs construct simple to complex deep burrows in soft sandy and/or muddy substrates. They can be found in sandy beaches, rubble flats, and in estuarine areas. They are nocturnal and are generalist scavengers and predators of small animals. "Ocypode" ghost crabs are found in tropical and subtropical regions throughout the world. Three species are found in the Atlantic Ocean and the Mediterranean Sea and one in the eastern Pacific coast of the Americas. The rest of the species are found in the western Pacific and the

neg: Lesser sand plover the greater sand plover, "Charadrius leschenaultii". Separating the species may be straightforward in mixed wintering flocks on an Indian beach, where the difference in size and structure is obvious; it is more difficult to identify a lone vagrant to western Europe, where both species are very rare. The problem is compounded in that the Middle Eastern race of greater sand plover is the most similar to the lesser. The lesser usually has darker legs, a white forehead, and a more even white wing bar than the greater. The lesser sand plover's feeds on insects, crustaceans and annelid worms, which are

neg: Mangrove horseshoe crab six pairs of appendages. The first pair, the chelicerae, are relatively small and placed in front of the mouth. They are used to place food in it. The remaining five pairs of legs are placed on either side of the mouth and are used for walking/pushing. These are the pedipalps (first pair) and the pusher legs (remaining four pairs). Most of the appendages have straight, scissor-like claws, but in males the first and second pair of walking legs have strongly hooked "scissors", which are used for grasping the female during mating. Located behind their legs are book gills. These gills

neg: Holmipterus one on each side. These walking legs are characteristic of most carcinosomatids in which the legs were flattened and with the venter (abdomen) turned anteriorly. They were different from the highly differentiated legs of "Megalograptus". The spines of the walking legs were striated with narrow and longitudinal ridges along the back of the curved part. The swimming legs are known for a paddle retaining the sixth and seventh segments. The triangular lobe of the sixth joint was very long with linear scales along most of the posterior border which grade into serrated scales at the distal end. The seventh joint

neg: Stenopus scutellatus Stenopus scutellatus Stenopus scutellatus, commonly known as the gold coral banded shrimp or golden coral shrimp, is a boxer shrimp, a shrimp-like decapod crustacean belonging to the family Stenopodidae. It is found in suitable habitats in the western Atlantic and the Caribbean Sea. "Stenopus spinosus" can grow up to long, and has a yellow spiny carapace and abdomen and long white antennae. The third pair of pereiopods (walking legs) are spiny and bear long claws and are much larger than the other pairs. They are boldly barred in red and white while the other legs are yellow. The tip of

neg: Fin already present in the swimming fin of a fish. In 2011, researchers at Monash University in Australia used primitive but still living lungfish "to trace the evolution of pelvic fin muscles to find out how the load-bearing hind limbs of the tetrapods evolved." Further research at the University of Chicago found bottom-walking lungfishes had already evolved characteristics of the walking gaits of terrestrial tetrapods. In a classic example of convergent evolution, the pectoral limbs of pterosaurs, birds and bats further evolved along independent paths into flying wings. Even with flying wings there are many similarities with walking legs, and core

neg: Amblypygi three eyes each further back on each side. Amblypygids have raptorial pedipalps modified for grabbing and retaining prey, much like those of a mantis. The first pair of legs act as sensory organs and are not used for walking. The sensory legs are very thin and elongate, have numerous sensory receptors, and can extend several times the length of body. Amblypygids have eight legs, but use only six for walking, often in a crab-like, sideways fashion. The front pair of legs are modified for use as antennae-like feelers, with many fine segments giving the appearance of a "whip". When a

neg: Biomechanics of sprint running has been found that sprinters have to apply a large amount of force onto the ground to achieve the desired acceleration, rather than taking more rapid steps. Human legs during walking have been mechanically simplified in previous studies to a set of inverted pendulums, while distance running (characterized as a bouncing gait) has modeled the legs as springs. Until recently, it had been long believed that faster sprinting speeds are promoted solely by physiological features that increase stride length and frequency; while these factors do contribute to sprinting velocities, it has also been found that the runner’s ability to produce

neg: Terrestrial locomotion addition to their six more-standard arthropod legs have a similar form to those of velvet worms, and suggest a distant shared ancestry. Animals show a vast range of gaits, the order that they place and lift their appendages in locomotion. Gaits can be grouped into categories according to their patterns of support sequence. For quadrupeds, there are three main categories: walking gaits, running gaits, and leaping gaits. In one system (relating to horses), there are 60 discrete patterns: 37 walking gaits, 14 running gaits, and 9 leaping gaits. Walking is the most common gait, where some feet are on the

neg: Phrynus marginemaculatus Phrynus marginemaculatus Phrynus marginemaculatus is a species of amblypygid found in southern Florida, the Bahamas, Cuba, and Hispaniola. They are nocturnal predators that hide during the day in small retreats. The body of "P. marginemaculatus" can measure up to long, but its front legs can reach long. It has eight legs, of which six are used for walking and the first two are employed as sensory organs for detecting prey and navigating their environment. Its cephalothorax is wider than it is long and is outfitted with eight eyes. One pair of eyes is located in front and three more pairs

neg: Medauroidea extradentata Medauroidea extradentata Medauroidea extradentata, commonly known as the Vietnamese or Annam walking stick, is a species of the family Phasmatidae. They originate in Vietnam and are commonly found in tropical forests there. They eat a variety of foliage, though in captivity they commonly eat blackberry bramble, hawthorn, oak, red maple and rose. Vietnamese walking sticks are approximately 4-5 inches (10–12 cm) in length. Their heads are elongated and oval shaped with thread-like antennae. Their chewing mouthparts are specially adapted for eating plant material. Along its thorax are a number of small pointed bumps. Their middle set of legs show small

neg: Mastigoproctus colombianus Mastigoproctus colombianus Mastigoproctus colombianus is a whip scorpion species found in Colombia, South America, near west deserts areas. "Mastigoproctus colombianus" range from in length. Color brown and red-end legs. Like the related orders Schizomida, Amblypygi and Solifugae, uropygids use only six legs for walking, having modified their first two legs to serve as antennae-like sensory organs. Whip scorpions have no venom glands, but they do have glands near the rear of their abdomen that can spray a combination of acetic acid and octanoic acid when they are bothered. The acetic acid gives this spray a vinegar-like smell, giving rise to

neg: Amphipoda to baleen whales. They are the only parasitic crustaceans which cannot swim during any part of their life cycle. Most amphipods are detritivores or scavengers, with some being grazers of algae, omnivores or predators of small insects and crustaceans. Food is grasped with the front two pairs of legs, which are armed with large claws. More immobile species of amphipods eat higher quantities of less nutritious food rather than actively seeking more nutritious food. This is a type of compensatory feeding. This behaviour may have evolved to minimise predation risk when searching for other foods. "Ampithoe longimana", for example, is

neg: Krill "E. longirostris", "E. triacantha" and "E. vallentini". Krill are crustaceans and have a chitinous exoskeleton made up of three tagmata: the cephalon (head), the pereion (fused to the cephalon to form a cephalothorax), and the pleon. This outer shell of krill is transparent in most species. Krill feature intricate compound eyes; some species adapt to different lighting conditions through the use of screening pigments. They have two antennae and several pairs of thoracic legs called pereiopods or thoracopods, so named because they are attached to the thorax; their number varies among genera and species. These thoracic legs include feeding legs

neg: Fish fin already present in the swimming fin of a fish. In 2011, researchers at Monash University in Australia used primitive but still living lungfish "to trace the evolution of pelvic fin muscles to find out how the load-bearing hind limbs of the tetrapods evolved." Further research at the University of Chicago found bottom-walking lungfishes had already evolved characteristics of the walking gaits of terrestrial tetrapods. In a classic example of convergent evolution, the pectoral limbs of pterosaurs, birds and bats further evolved along independent paths into flying wings. Even with flying wings there are many similarities with walking legs, and core

neg: Pleocyemata pleopods (swimming legs) until the zoea larvae are ready to hatch. It is this characteristic that gives the group its name. Pleocyemata also possess a lamellar gill structure as opposed to the branched found in Dendrobranchiata. The earliest fossil representative is the Devonian "Palaeopalaemon". Pleocyemata Pleocyemata is a suborder of decapod crustaceans, erected by Martin Burkenroad in 1963. Burkenroad's classification replaced the earlier sub-orders of Natantia and Reptantia with the monophyletic groups Dendrobranchiata (prawns) and Pleocyemata. Pleocyemata contains all the members of the Reptantia (including crabs, lobsters, crayfish, and others), as well as the Stenopodidea (which contains the so-called "boxer

neg: Ghost crab (antennular flagella) are small or rudimentary. They fold back into the body diagonally or almost vertically. The plate between them (the interantennular septum) is broad. The third pair of mouth appendages (maxillipeds) completely cover the mouth opening. A small orifice with edges thickly fringed with hair is found between the bases of the second and third pairs of walking legs. Ghost crab species can be most reliably identified by means of the area where they were recovered, the presence of "horns" (styles) on their eyestalks (exophthalmy), the pattern of stridulating (sound-producing) ridges on the inside surface of the palms of

neg: Concornis "Concornis lacustris" are by and large conjectural. Its legs and flight apparatus suggest it was a truly multifunctional generalist bird able to bound through vegetation, run on the ground, and fly equally well. Compared to living birds adapted to each of these ecological niches, it would have certainly been inferior. It was found in an aquatic environment, suggesting it occupied at least partly a "shorebird" niche, and given its size would presumably have fed on small invertebrates like insects or crustaceans. There were terrestrial predators around in its habitat - including its non-avialan theropod relatives and crocodilians - from which

neg: Titanophyllum Titanophyllum "T. spiliarum" specimens measure 17 – 33 mm in length and 1 to 1.4 mm wide. The pale yellow body consists of a head followed by 47-61 body segments with legs, 1-2 legless segments, ending in a telson (legless, last body segment). The walking legs are about 80% the body width. Eyes are absent. Like other members of the Julida, mature males have two pairs of highly modified legs, the gonopods, in place of the 8th and 9th pair of walking legs. Unusual among Julid millipedes, the telson possesses a small, forward-projecting hook on the hypoproct or subanal scale

neg: Libinia dubia other organisms as camouflage. There are two small stalked eyes and between these the carapace extends forward in a forked rostrum. There are five pairs of long, thin, jointed walking legs. The front pair end in rather small pincers and the terminal joint of the others legs is a curved claw. The longnose spider crab may be confused with the portly spider crab, "Libinia emarginata", but that species usually has nine spines on the margin at each side of the shell. The longnose spider crab is found on the eastern seaboard of the United States at depths down to about

neg: Gerris lacustris Gerris lacustris Gerris lacustris, commonly known as the common pond skater or common water strider, is a species of water strider, found across Europe. Water striders vary in length ranging between and in size. Their body shape is very slender and elongated. They have six legs; the first pair is short and stubby while the other two pairs are thin and elongated which are used for moving over the water surface which we call "walking on water". The first pair of legs is used for holding its prey, the middle pair propels the bug along the surface of the water

neg: Shrimp crustacean which resembles a shrimp tends to be called one. They swim forward by paddling with swimmerets on the underside of their abdomens, although their escape response is typically repeated flicks with the tail driving them backwards very quickly. Crabs and lobsters have strong walking legs, whereas shrimp have thin, fragile legs which they use primarily for perching. Shrimp are widespread and abundant. There are thousands of species adapted to a wide range of habitats. They can be found feeding near the seafloor on most coasts and estuaries, as well as in rivers and lakes. To escape predators, some species

neg: Onychopoda Onychopoda Onychopoda are a specialised suborder of branchiopod crustaceans, belonging to the order Cladocera. The suborder Onychopoda is "one of the most morphologically distinctive groups of cladocerans". They have only four pairs of legs, compared to five or six pairs in Ctenopoda and Anomopoda. Unusually among branchiopod crustaceans, Onychopoda share with Haplopoda the presence of segmented appendages, which are used for grasping prey. Most species of Onychopoda live in the waters of the Ponto-Caspian basin (Caspian Sea, Aral Sea, Black Sea including Sea of Azov), in remnants of the ancient Paratethys ocean. Some other species live in fresh water or

neg: Spectacled petrel the story of his walking on water. This is in reference to the petrel's habit of appearing to run on the water to take off. The spectacled petrel eats cephalopods, fish, and crustaceans. This petrel breeds annually and will lay one egg in its nest, which is situated in wet heath above . Their nests are burrows along the banks of rivers, and also in marshes. The spectacled petrel is pelagic and during non-breeding season the majority of these petrels can be found off the coast of southern Brazil. They also range east to the west coast of southern Africa,

neg: Insect Their muscles are able to contract multiple times for each single nerve impulse, allowing the wings to beat faster than would ordinarily be possible. Having their muscles attached to their exoskeletons is more efficient and allows more muscle connections; crustaceans also use the same method, though all spiders use hydraulic pressure to extend their legs, a system inherited from their pre-arthropod ancestors. Unlike insects, though, most aquatic crustaceans are biomineralized with calcium carbonate extracted from the water. The nervous system of an insect can be divided into a brain and a ventral nerve cord. The head capsule is made up

neg: Hepatic caecum found in certain crustaceans. In some insects, such as the grasshopper, several pairs of hepatic caeca secrete enzymes into the stomach where they assist in the digestive process. Hepatic caecum Hepatic caecum or hepatic cecum is a name used in describing various physiological structures in some crustaceans, insects and cephalochordates. "Hepatic" refers to the liver, and the hepatic caecum may perform some functions that are analogous to the functions of the liver in vertebrates. A digestive organ called the hepatic caecum is found in the cephalochordate amphioxus, or lancelet. The hepatic caecum of the amphioxus is a presumed homologue of

neg: Walking gait does not meet all the criteria of running, although the elephant uses its legs much like other running animals, with the hips and shoulders falling and then rising while the feet are on the ground. Fast-moving elephants appear to 'run' with their front legs, but 'walk' with their hind legs and can reach a top speed of . At this speed, most other quadrupeds are well into a gallop, even accounting for leg length. Walking fish (or ambulatory fish) are fish that are able to travel over land for extended periods of time. The term may also be used

neg: Australasian bittern sides of neck. Under surface buff, striped with brown. The face skin is a dull green as are the legs and feet, it possesses a dark brown bill, yellow eyes, and the base of the lower mandible is green-yellow. It feeds on aquatic animals such as frogs, eels and freshwater crustaceans. It is a solitary nester on the ground in dense wetland vegetation on trampled reeds and other plants. It is found in south-western and south-eastern Australia, Tasmania, New Zealand, New Caledonia and Ouvea. Populations in Australia and New Zealand have declined in the 20th century. It is a cryptic

neg: Branchiopoda front to back, and each bears a pair of legs which also carry gills. A strong muscle can close the two halves of the shell together. Cladocera is an order of small crustaceans commonly called water fleas. Around 620 species have been recognised so far, with many more undescribed. They are ubiquitous in inland aquatic habitats, but rare in the oceans. Most are long, with a down-turned head, and a carapace covering the apparently unsegmented thorax and abdomen. There is a single median compound eye. Most species show cyclical parthenogenesis, where asexual reproduction is occasionally supplemented by sexual reproduction, which

neg: Facultative bipedalism Facultative bipedalism A facultative biped is a animal that is capable of walking or running on two legs (bipedal), as a response to exceptional circumstances (facultative), while normally walking or running on four limbs or more. In contrast, obligate bipedalism is where walking or running on two legs is the primary method of locomotion. Facultative bipedalism has been observed in several families of lizards and multiple species of primates, including sifakas, capuchin monkeys, baboons, gibbons, and chimpanzees. Different facultatively bipedal species employ different types of bipedalism corresponding to the varying reasons they have for engaging in facultative bipedalism. In primates,

neg: Arthropod leg while the internal branch is known as the endopod or endopodite. Other structures aside from the latter two are termed exites (outer structures) and endites (inner structures). Exopodites can be easily distinguished from exites by the possession of internal musculature. The exopodites can sometimes be missing in some crustacean groups (amphipods and isopods), and they are completely absent in insects. The legs of insects and myriapods are uniramous. In crustaceans, the first antennae are uniramous, but the second antennae are biramous, as are the legs in most species. For a time, possession of uniramous limbs was believed to be a

neg: Portunus sayi The carapace, claws and legs are usually pale brown with large white or flesh-coloured blotches but the brown colour may have a purplish or greenish tinge. This crab, like other members of its family, is specially adapted for swimming rather than walking as its fourth pair of legs are modified with flattened, paddle-like surfaces. It swims sideways rather than forwards and can move surprisingly swiftly. "Portunus sayi" occurs in the western Atlantic Ocean and Caribbean Sea. Its range extends from Nova Scotia and the Gulf of Maine to southern Florida, the Bahamas and the Gulf of Mexico. It is found

neg: Gulf ghost crab not more than two and a half times the length of the carapace. The fourth pair is relatively smaller and weaker in comparison to the other three pairs, reaching only to the middle of the propodus of the third pair. The mera and carpi of all the legs are naked, but the propodi possess fur-like bristles (setae) on for the first three walking leg pairs varying by sex. In males, the propodi of the first and second pair of walking legs have their upper forward surfaces covered with setae. The propodi of the third pair of walking legs only have

neg: Eumalacostraca Eumalacostraca Eumalacostraca is a subclass of crustaceans, containing almost all living malacostracans, or about 40,000 described species. The remaining subclasses are the Phyllocarida and possibly the Hoplocarida. Eumalacostracans have 19 segments (5 cephalic, 8 thoracic and 6 abdominal). This arrangement is known as the "caridoid facies", a term coined by William Thomas Calman in 1909. The thoracic limbs are jointed and used for swimming or walking. The common ancestor is thought to have had a carapace, and most living species possess one, but it has been lost in some subgroups. Calman identified the following features as distinguishing eumalacostracan crustaceans: "Carapace

neg: The Walking Man self-possessed classical posture with both feet turned out, Rodin uses the kind of step that brings all power to bear on the moment’s work The statue has served as the inspiration for the works of other artists, such as Carl Sandburg, who described it in his 1916 poem, "The Walking Man of Rodin": THE WALKING MAN OF RODIN Legs hold a torso away from the earth. And a regular high poem of legs is here. Powers of bone and cord raise a belly and lungs Out of ooze and over the loam where eyes look and ears hear And arms