into account allometry allometric effects. The relationship, expressed as a formula, has been developed ... Moore, J. 1999 http weber.ucsd.edu jmoore courses allometry allometry.html Allometry , University ... more details
italictitle Taxobox name Lestodon fossil range Pleistocene image Lestodon armatus Ghedo.JPG image width 250px image caption Lestodon armatus skeleton regnum Animal ia phylum Chordata classis Mammalia superordo Xenarthra ordo Pilosa familia Mylodontidae familia authority Theodore Gill Gill , 1872 genus extinction Lestodon genus authority Paul Gervais Gervais , 1855 species L. armatus Lestodon is an extinct genus of megafaunal ground sloth from South America during the Pleistocene period. Its fossil remains have been found in Argentina , Paraguay , Uruguay , and Bolivia . 15 feet from snout to tail tip, it is estimated to have weighed between two and four tons. It was a herbivore and primarily fed on the grasses on the South American plains and is thought to perhaps have used its semi bipedal stance to obtain foliage from trees. Lestodon is placed as member of the Mylodontidae as indicated by the lobed form of the last tooth in the dentition. The genus name Lestodon derives from the Greek for robber tooth. Image Lestodon armatus.JPG thumb left Right foot of Lestodon armatus Image Lestodon armatus MLP.jpg thumb left Mounted skeleton of Lestodon armatus on display at the Museo de La Plata Evolutionary Adaptations Cranial The skeleton morphologically reflects its evolutionary history as well as its daily activities. At the caudal end, the sloth s head connects to its neck with a class one lever. The skull is two to three orders of magnitude larger than living species of sloth, but the muzzle itself shows highly positive allometry to the size of the skull in comparison to modern sloths and even other megafauna of the same order Pilosa . L. Armatus had a large, blunt, and square mandible well adapted for foliage consumption. Its muzzle and dentition show a significant adaptation to this diet. The shape of the muzzle aided the ground sloth in the grazing necessary to sustain the metabolic activity of its large body square, flat muzzles are associated with bulk feeders while ... more details
Taxobox image Camponotus vagus.jpg regnum Animal ia phylum Arthropod a classis Insect a ordo Hymenoptera familia Formicidae genus Camponotus species C vagus binomial Camponotus vagus binomial authority Giovanni Antonio Scopoli Scopoli , 1763 Camponotus vagus is a species of large, black, Palaearctic West Palaearctic carpenter ant with a wide Range biology range that includes much of Europe , a large area of Asia , and part of Africa . ref name nor http www.nhm.uio.no entomologi journals nje 2008 1 abs NJE 55 nr1 cut 20105.pdf Norwegian Journal of Entomology ref ref name eol http eol.org pages 398021 Encyclopedia of Life Camponotus vagus Scopoli, 1763 ref Description File Formicidae Camponotus vagus.JPG thumb 250px left Camponotus vagus Lateral view Camponotus vagus is a relatively distinctive species that is easily identified by its large size, uniform black colour, and the long and dense body Seta hairs on its exoskeleton . A Eusociality eusocial insect , individuals have continuous Allometry allometric variation in size and morphology biology morphology to facilitate Task allocation and partitioning of social insects task allocation and partitioning of work . Workers are 6 12 mm in length. ref name nor The larger major workers act as guards for in defence of the colony and protect the smaller minor workers when the latter go foraging outside the nests. The powerful Mandible insect mouthpart mandible s of the major workers are capable of decapitating smaller arthropod s captured as food and dismemberment dismembering smaller ants of other species. ref http www.anthillwood.co.uk blackants2.htm Ant Hill Wood ref Diet C. vagus is known to be both carnivorous and aphid icolous living in a Mutualism biology mutualistic relationship with aphid s and feeding upon the Honeydew secretion honeydew these smaller insects release from the Rectum terminations of their Gastrointestinal tract alimentary canals . ref name nor ref http www.oeb.harvard.edu faculty pierce people ... more details
Italic title Taxobox name Cancer johngarthi regnum Animal ia phylum Arthropod a subphylum Crustacean Crustacea classis Malacostraca ordo Decapoda infraordo Crab Brachyura familia Cancridae genus Cancer genus Cancer species C. johngarthi binomial Cancer johngarthi binomial authority Carvacho, 1989 Cancer johngarthi is a species of crab that lives in the eastern Pacific Ocean from Mexico to Panama . It was separated from Cancer porteri C. porteri in 1989, and is the subject of a small scale fishery off Baja California peninsula Baja California . Distribution Cancer johngarthi lives along the Pacific Ocean Pacific coast of Mexico and Central America , from 29th parallel north 29 N at Guadalupe Island Isla Guadalupe to 7th parallel north 7 N in Panama , including southern parts of the Gulf of California Sea of Cortez . ref name Carvacho Description and taxonomic history Cancer johngarthi was only recognised as a separate species in 1989, its members having previously been treated under Cancer porteri C. porteri . ref name Carvacho cite journal author Alberto Carvacho year 1989 title Cancer johngarthi , n. sp. and Cancer porteri Bell Crustacea, Decapoda journal Proceedings of the Biological Society of Washington volume 102 issue 3 pages 613 619 url http biostor.org reference 74602 ref The specific name zoology specific epithet commemorates John Shrader Garth of the University of Southern California ref name Carvacho Garth had recorded C. porteri from Sinaloa , Mexico, in 1961. ref name Carvacho It differs from C. porteri chiefly in the paper shell texture of the carapace. C. johngarthi also has longer legs, and stouter claws, although the differences in claws are not clear in juvenile organism juveniles , due to differences in allometry . ref name Carvacho According to data from experimental fisheries, captured males varied in size from a carapace width of convert 98 mm to convert 176 mm abbr on , while females were slightly smaller, at convert 87 153 mm abbr on . ref na ... more details
TOC right Encephalization is defined as the amount of brain mass exceeding that related Brain to body mass ratio to an animal s total body mass . Quantifying an animal s encephalization has been argued to be directly related to that animal s level of intelligence . Aristotle wrote in 335 B.C. Of all the animals, man has the brain largest in proportion to his size. ref name RussellNorvigAI Also, in 1871, Charles Darwin wrote in his book The Descent of Man No one, I presume, doubts that the large proportion which the size of man s brain bears to his body, compared to the same proportion in the gorilla or orang, is closely connected with his mental powers. ref name Darwin1871reprintp145 In 2004, Dennis Bramble and Daniel Lieberman proposed that early Homo genus Homo were scavengers that used stone tools to harvest meat off carcasses and to open bones. They proposed that humans specialized in long distance running to compete with other scavengers in reaching carcasses. ref name running It has been suggested that such an adaptation ensured a food supply that made large Human brain brains possible. More encephalized species tend to have longer spinal shock duration. Encephalization may also refer to the tendency for a species toward larger brains through evolutionary time. Antropology Anthropological studies indicate that bipedal ism preceded encephalization in the human evolutionary lineage after divergence from the chimpanzee lineage. Compared to the chimpanzee brain, the human brain is larger and certain brain regions have been particularly altered during human evolution. ref name compchimp Most brain growth of chimpanzees happens before birth while most human brain growth happens after birth. ref name Heterochrony see Heterochrony ref Encephalization quotient see also Encephalization quotient math E CS r math In Snell s equation of simple allometry ref name Williams E is the weight of the brain, C is the cephalization factor and S is body weight and r is the exponenti ... more details
. Image Primate Testes Allometry Sexual Selection.jpg thumb right Testes mass of various species .... Torr, 1998, p. 52 See also div style column count 3 moz column count 3 webkit column count 3 Allometry .... A. Barton. 2001. Comparative methods for studying primate adaptation and allometry. Evolutionary ... more details
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