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98 Cards in this Set
- Front
- Back
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Phylum Echinodermata |
-have endoskeleton -Pentaradial symmetry (larvae are bilateral) -sea starts, brittle stars, sea urchins, sand dollars, sea cucumbers |
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Nervous system |
Nerve ring with branches-no centralization of function (lacks cephalization) |
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Endoskeleton |
-epidermis with spines covers endoskeleton -composed of calcium carbonate ossicles - May be tightly or loosely joined -all members have mutable collagenous tissues |
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Water-vascular system |
-radially organized -radial canal extends from each ring canal into each body branch -water enters through madreporite (flows through stone canal to ring canal |
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Tube Feet |
may or may not have suckers -Ampulia-muscular sac at base -used in movement, feeding, gas exchange |
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regeneration |
-many able to regenerate lost parts -some reproduce asexually by splitting |
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sexual repeoduction |
-Most reproduction is sexual -Gonochoric -gametes released into water -free-swimming larvae (each class has a characteristic type of larva) |
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5 extant classes |
1. asteroidea 2.Echinoidea (sea urchins and sand dollars) 3. Ophiuroidea (brittle stars) 4. Crinoidea (sea lillies and feather stars) 5. Holothuroidea (sea cucumbers) |
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Asteroidea |
-sea stars and sea daisies -most have 5 arms, some have multiples of 5 -Important predators in may marine systems (extend stomach to feed) |
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Echinoidea |
-sea urchins and sand dollars - lacks arms -double rows of tube feet -protective moveable spines |
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Ophiuroidea |
-brittle stars -largest class -arms are equal diameter their entire length -arms are easily autotomized (detached) |
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Crinodea |
sea lilies and feather stars |
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Holothuroidea |
-sea cucumbers -deposit feeders, lay on their "side" |
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Phylum Chordata |
-Chordates are dueterosome coelomates -nearest relatives are echinoderms (the only other major group of dueterostomes) -includes fishes, amphibians, reptiles, birds and mammals |
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Four characteristics of Chordates |
1. Dorsal, hollow nerve cord 2. Notochord (internal support, ,ay be replaced by a vertebral column) 3. Pharyngeal slits (Pharylngeal pouches present in all vertebrate embryos) 4. Postanal tail (improved locomotion) all chordates have all four of the structures at some point in their lives |
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Other characteristics of chordates |
Chordate muscles are arranged in segmented blocks called somites Most chordates have and endoskeleton against which the muscles work |
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Phylum Cordata can be divided into 3 subphyla |
1. Urochordata 2. Cephalochordata 3. Vertebrata The first two are invertabrates |
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Urochordata |
-Tunicates and salps (marine animals) - Larvae tadpole-like, have notochord and nerve cord (free swimming but do not feed) -Adults usually lose tail and notochord (immobile sessile filter feeders-many secrete a tunic-cellulose sac- that surrounds the animal |
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Subphylum Cephalochordata |
-Lancets(aka amphioxus) are scaleless Chordates -Notochord persists through out animals life -spend most of their time partly buried - no distinguishable head -feed on plankton using cilia-generated currents -closest relatives to vertebrates |
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Subphylum Vertebrata |
-chordates with a spinal column -distinguished from nonvertabrates by -vertebral column-encloses and protects the dorsal nerve chord - Notochord reduced, contributes to invertebral discs -head-distinct cephalization and well differentiated possessing sensory organs - Vertebrates also have a Neural crest -A unique group of embryonic cells that migrate during development to form many vertebrate structures -Internal organs and a closed circulatory system -ENdoskeleton made of cartilage or bone (made possible great size and extraordinary movement) |
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progression of vertabrates |
-about 545MYA- mouth at one end, fin at the other -jawed fish soon became dominant -amphibians came to land -birds and mammals became dom. after Cretaceous mass extinction |
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Fishes |
-most diverse vertebrate group
-over half of all vertabrates -provide evolutionary base for invasion of land |
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Characteristics of fishes |
1. Vertebral column (hagfish and lamprey exceptions) 2. Jaws and paired appendages (hagfish and lemapreys exceptions) 3.internal gills 4. single loop blood circulation (no pulmonary) 5.Nutritional deficiencies-innability to synthesize aromatic amino acids has been inherited by all their vertebrate descendants |
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Agnatha-first fishes had mouths with no jaw |
Hagfish- deep sea, eye-less, produce slime
Lampreys- some are parasitic of larger fish -round mouth and keratinized "teeth" for attaching to fish -keratinized tongue to rasp at host's flesh |
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The development of jaws
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late Sirulian period, evolved from anterior gill arches made of cartilage
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Class Chondrichthyes |
-sharks, skates and rays -becamse dom sea predators in Carboniferous period(360-280 MYA) -cartilage skeleton calcified eith granuels of calcium carbonate (light, strong skelton-improved bouyancy along with oily liver) |
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First vertabrates to develop teeth |
Sharks -evolved from rough placoid scales on mouth's skin -easily lost but continuously replaced |
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Sharks have |
fully developed lateral line system (series of sensory organs under the skin that detects changes in pressure waves)(bony fish also have) Ampullae of Lorenzini-detects weak electrical field |
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Shark reproduction |
-eggs are fertilized internally and most pups are born alive (a few species lay fertilized eggs) -long gestation period and few offspring makes it difficult to recover from population declines or overfishing |
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Bony Fishes |
Evolved about same time as sharks (400MYA) but have a heavy internal skeleton made of bone -most species rich group of all vertebrates(>30,000 living species) -significant adaptations include operculum (gills cover and swim bladder |
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Operculum |
-hard plate over gills -flexing plate permits water pumping over gills -efficient bellows system when stationary |
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Swim bladder |
gas-filled sac that allows bony fishes to reulate their bouyant density - in most modern fishes fills and drains gases internally |
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Two groups of bony fish |
Ray-finned and Lobefinned |
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Ray-finned fish |
parallel bony rays support and stiffen each fin - majority of modern fish -no muscle within fins |
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Lobe-finned fish |
-paired fins consist of long fleshy muscular lobe -supported by a central core of bones with fully articulated joints -includes lungfishes and coelacanth -almost certainly the amphibian ancestor |
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Tiktaalik |
-transitional fossil between true fish and Ichthyostega (true amphibian) -has gills and sclaes like a fish but neck and limbs like an amphibian -shoulder forearm and wrist bones like amphibians but with a lobed fin at the end instead of toes |
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Ichthyostega |
-amphibians evolved from lobe-finned fish -sturdy forelegs-flippershaped hindlegs (moved life a seal) -Long broad overlapping ribs formed a solid cage for lungs and heart |
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Class Amphibia |
first vertebrates to walk on land direct descendants of fish |
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5 distinguighin characteristics of amphibians |
1. legs 2. lungs 3. cutaneous respiration (supplement lungs) 4.Pulmonary veins-separate pulmonary circuit allows higher pressure to blood tissues 5. Partially divided heart (2 atria)- improves separation of pulmonary and systemic circuits |
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adaptations needed for invasion of land |
Legs- to support body weight lungs-to extract oxygen from air redesigned heart and circulatory system-to drive larger muscles reproduction in still water-to prevent egg drying desiccation prevention system |
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3 modern amphibian Groups (5,670 species in 37 different familes) |
Order Anura- "without tail" Order Caudata- "visible tail" Oder Apoda- "without legs" |
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Order Anura
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frogs and toads Frogs have smooth, moist skin and long legs (live in or near water, aquatic tapdpole stage begfore metamorphosis into adult) Toads have bumpy, dry sking and short legs (dry environments, not monophyletic group-convergence withing Anura) |
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Anura reproduction |
-eggs laid in water-lack watertight membrane -eggs fertilize externally -tadpole-swimming larval stage -gradual metamorphosis into adult form |
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Order Caudata |
-long bodies, tails and smooth moist skin -live in moist places -eggs are ferilized internally with transfer of sperm packet (spermatophore) -larvae similar to adults |
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Order Apoda (caecilians) |
-tropical, burrowing amphibians -legless with small eyes and jaws and teeth -fertilization is internal |
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Class Reptilia (over 7,000 living species) 3 main features |
1. watertight amniotic eggs 2. Dry skin covering body prevents water loss 3. Thoracic breathing, increases lung capacity (different from mammals) |
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Amniotes |
birds, reptiles and mammals |
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The amniotic egg has 4 extra-embryonic membranes inside shell |
-Chorion- outermost layer allows gas exchange -Amnion-Encases embryo in fluid-filled cavity -Yolk sac-provides food -Allantois- contains excreted wastes from embryo |
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Reptiles are distinguished by temporal openeings the types are... |
0-anapsids-turtles (may have secondarily lost holes) 1-synapsids-led to mammals 2-diapsids-led to most modern reptiles |
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Synapsids that rose to dominance first |
Pelycosaurs-first land vertebrates to kill beasts their own size Therapsids- may have been endothermic, mammal like reptiles, extinct 170 MYA, one group survived and has living descendants today (mammals) |
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First bipedal vertebrates |
Archosaurs- gave rise to crocodiles, pterosaurs, dinosaurs and birds |
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Dinosaurs |
-dominated for over 150 million years -extinct 65MYA -birds descended -asteroid impact |
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Two important characteristics of modern reptiles |
-internal fertilization -improved circulation - oxygen is provided to body more effeiciently (systemic circuit) - in most septum in heart extended to create partial ventricular wall -in crocodiles, birds and mammals (arose independently) have complete septum for divided 4-chambered heart |
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Ectothermic |
-obtain heat from external sources -regulatebody temperature by moving in and out of sunlight -compare to endothermic animals that also generate their own heat internally ALL LIVING REPTILES ARE ECTOTHERMIC |
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4 living orders of reptiles, approx. 7000 species, live worldwide except in coldest areas |
-chelonia (turtles and tortoises) -Rhynchocephalia (tuataras) -Squamata (lizards and snakes) Crocolylia (crocodiles and alligators) |
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Order Chelonia |
-differ from all others because of shell (Carapace-dorsal, Plastron-ventral) -lack teeth but have sharp beaks -marine turtles return to land to lay eggs |
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Order Rhynchocephalia |
-only two species of tuataras -large lizard-like animals about half a meter long -only found on islands near New Zealand -parietal eye- eye with lense and retina concealed under layer of scales |
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Order Squamata |
-Lizards-3800 species- many have ability to regernate lost tail -Snakes-3000 species-lack limbs, moveable eyelids and external ears, all are carniverous |
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Order Crocodylia |
-25 species of large, primarily aquatic carinverous reptiles -bodies well adapted to stealth hunting (eyes on tope of head, nostrils on top of snout, emormous mouth, strong necks) resemble birds more than any other living reptiles (build nests and care for young, 4-chambered hearts) |
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Crocodiles |
typically nocturnal tropical and subtropical regions |
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Alligators |
-only two species |
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Class Aves |
birds are most diverse of terrestrial vertebrates (28 orders, 166 families, about 8600 species) success lies in the unique structure in a feather still retain many reptilian traints (amniotic eggs and scales on legs) but lack teeth and tails of reptiles |
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Two major distinguishing traits of birds |
-feathers- modified scales of keratin -provide lift for flight, conserve heat and used for display -flight skeleton- bones are thin and hollow -many are fused for rigidity (keeled sternum) to anchor strong flight muscles |
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Feathers |
-originally evolved from reptile scales -linked structure provides a continuous surface and sturdy but flexible shape -feathers evolved in reptiles prior to birds, probably for insulation and display not flight (fossil feathers in amber indicate that feathers were colorful |
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Archaeopteryx |
-first known bird - had skull with teeth, long reptilian tail -feathers on wings and tail forelimbs identical to those of theropods |
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Birds have 3 evolutionary novelties |
- feathers -hollow bones -Physiological adaptations for flight |
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Physiological adaptations for flight |
-efficient repiration -unidirectional ventilatio (air passes all the way through lungs in one direction) -Endothermy- body temperature permits higher metabolic rate -Efficient circulation (4-chambered heart so muscles receive fully oxygenated blood, rapid heartbeat) |
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Modern Birds |
-28 orders of birds *most ancient are flightless, like ostrich * next are geese, ducks and waterfoul * Passeriformes comprise about 60% of species today |
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Class Mammalia |
about 4500 species (least of the five vertebrate classes) Two main traits: Hair- long keratin rich filaments used for unsulations, camoflouge, sensory structure and display Mammary Glands- Females possess mammary glands that secrete milk other notable features Endothermy and Placenta |
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Specific adaptations in come groups of mammals |
1. specialized teeth 2.Digestion of plants 3. Development of hooves, nails, antlers and horns 4.Flying mammals |
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Specialized teeth |
- different types of teeth are highly specialized to match particular eatcing habits -incisors, canines, premolars and molars -contrast carnivore teeth to herbivore teeth |
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Digestion of plants |
-herbivorous mammals rely on mutualistic partnerships with bacteria for cellulose breakdown -Ruminants with multiple stomach chambers -Rabbits with enlarged caecum |
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Development of hooves, nails, antlers and horns |
-Hooves are specialized keratin pads (ungulates) -Horns- are bone surrounded by keratin (cattle, sheep, not rhinos) -Antlers are made of bone, not keratin and are shed (deer) |
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Flying mammals |
Bats -only mammals capable of powered flight -wing is leathery membrane of skin and muscle stretched over 4 finger bones -Navigate in the dark by echolocation |
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History of Mammals |
-been around since about 220 MYA -tiny shrew-like, insect eating, tree-dewlling creatures, may have been nocturnal based on large eye sockets -reached maximum diversity in Tertiary period (65-2MYA) -after mass extinction of dinosaurs and has been declining over the last 15 million years |
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2 subclasses of mammalia |
Prototheria and Theria |
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Prototheria |
-most primative -lay shelled eggs -only living group is monotremes |
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Theria |
- viviparous-young are born alive -two living groups Marsupials or pouched Placental mammals |
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Monotremes |
lay shelled eggs like reptiles have single opening (cloaca) for feces, urine and reproduction only 3 living species (duck-billed platypus and 2 echidna species) |
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Marsupials |
-Major difference is pattern of embryonic developement -short lived placenta, after birth newborn crawls into marsupial pouch, latches onto nipple and continues to develop opossumis only marsupial in north america, others are isolated to australia |
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Placental Mammals |
produce a true placenta that nourishes embryo throughout it's development -forms from both fetal and maternal tissues - young undergo a considerable period of development before they are born -includes most living mammals |
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Evolution of Primates |
-gave rise to our own species -evolved two features to survive in an arboreal environment -grasping fingers and toes (many with opposable thumbs) - binocular vision (eyes are front facing with overlapping fields of vision to allow for proper distance judgement) |
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Approx 40 MYA primates split into two groups |
Prosimians- only a few left today, lemurs, lorises and tarsiers, large eyes with increased visual acuity and mostly nocturnal Anthropoids |
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Anthropoids |
-includes moneksy, apes and humans -almost all diurnal- change in eye design includes color vision -expanded brains -live in groups with complex social interactions (care for young for extended period, long period of learning and brain development) |
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about 30-40 MYA (primate evolution) |
-new world monkeys migrated to South America by raft or landbridge (all arboreal many have prehensiles tail) -Old World Monkeys and hominids remained in Africa (no prehensile tails) |
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Hominoids |
include Apes- gibbon, orangutan, gorillas, chimpanzees, -larger brains than monekys and lack tails -paraphyletic group- some are closely related to hominids (chimps and bonobos) Hominids- humans -soon after gorilla lineage diverged, the common ancestor of all hominids split off from the chimpanzee line to begin the evolutionary journey leading to humans |
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Apes vs hominids |
-common ancestor thought to have been an arboreal climber -apes probably evolved knuckle-walking at least twice after the split with the human line -hominids became bipedal-walking upright *humans did not evolve from a knuckle walking ancestor |
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Apes vs. Hominids differences related to bipedal locomotion |
human vertebral column is more curved (lower lumbar on humnas) spinal cord exits from bottom of skull rather than the back like an ape humans carry much of the body's weight on the lower limb |
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Early Hominids Australopithecus |
-7 species -older and smaller brained -Fossil "lucy" -Gave rise to genus Homo |
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Characteristics of Australopithecines |
-weighed about 18 Kg -about 1m tall -hominid dentition -brains no larger than those of apes -walked upright |
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Bipedalism |
-seems to evolved as australopithecus left the forests for grasslands and open woodland -extends back 4MYA but substantial brain expansion not until 2 MYA -the why is controversial some theories -more energetically efficient - frees forelimbs for carrying -raises eyes |
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Genus Homo |
evolved from autralopithecus about 2MYA- -thought to be most directly from australopithecus afarensis) -in the 1960 hominid bones were found near stone tools in Africa- called homo habilis, close resemblance to Austropithecus but larger brain |
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in 2004 a new species was discovered in Indonesia Homo florensiensis "hobbit" |
-youngest fossils only 15000 yrs old -short stature may be due to mammals generally being smaller on islands -coexisted and preyed on a mini-elephant -believed to be more closely related to H. erectus than H. sapiens |
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Modern Humans |
-first appeared in Africa about 600,000 years ago -three species *H. heidelbergensis-coexisted with H. erectus *H. neanderthalensis-shorter and stocker than modern humans *H. sapiens- "wise man" -some lump all three into homo sapiens |
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Neanderthals |
-Made diverse tools -took care of sick and buried dead -first evidence of symbolic thinking -abruptly disappeared about 34,000 years ago |
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Cro-Magnons |
-two species probably interbred -complex social organization -elaborate cave paintings -thought to have full language capabilities |
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Homo Sapiens |
-only surviving hominid -progressive increase in brain size -refined and extended conceptual though -use of symbolic language -effective making and use of tools -extensive cultural experience - We change and mold our world rather than change evolutionarily in response to the environment |
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Human Races |
-Humans have differentiated their traits as they have spread -all humas are capable of mating with one another to produce fertile offspring -humans are visually oriented so we rely on visual cues (primarily skin color) to define races -constant gene flow has prevented subspecies of humans from forming -groupings based on genetic similarity are different from those based on skin color (current studies use relatedness and migration patterns to understand human evolution using mitochondrial and nuclear DNA |
