Vertebrates Flashcards
are of immense importance in aquatic and terrestrial ecosystems from the Ordovician onwards.
They are commonly present as predators and scavengers, becoming almost ubiquitous in modern faunas.
Vertebrates
the reinforced rod that runs down the animal’s back, is what makes it unique. In vertebrates, this often mineralizes to create a backbone that encircles a lengthy nerve sheaf.
chordate notochord
In all skeletonized vertebrates the substance employed is calcium phosphate (CaP04), combined with an organic material used as a
template
The first vertebrates are Cambrian in age and include conodont teeth and rare fish. A close ancestor of vertebrates is the Burgess Shale animal
Pilzaia
Vertebrates include fish, amphibians, reptiles, dinosaurs, mammals, and birds.
The earliest vertebrates were ____, and all of them were marine
fish
Most of these early fish lacked jaws.
Jaws evolved in the Silurian and this group, sometimes known as
gnathostomes
Primitive gnathostomes
cartilaginous
bony fish
several extinct groups fish
placoderms
acanthodians
It allows them to extend their jaws beyond their resting position, significantly increasing their reach and ability to capture prey or manipulate objects.
Jaw Protrusion
are tetrapods that lay eggs in water.
ancestral group to all of the other tetrapods, including reptiles, dinosaurs, and mammals, as well as birds.
AMPHIBIANS
The most likely ancestors of amphibians, and all other tetrapods, are a group of extinct lobefin fish known as
rhipidistians
Reptiles evolved from amphibians during the Carboniferous.
Their key innovation is the ability to lay eggs on land.
These amniotic eggs are a life support system for the embryo away from water
Amniotes
One possible early amniote is ____________, a small tetrapod found in a Carboniferous volcanic lake deposit from the Midland Valley of Scotland.
Westlothiana
The earliest well-known reptile is called ___________ and is found in the hollow tree stumps of a Carboniferous fossil forest in eastern Canada.
Hylonomus
Carboniferous origin, this is the primitive group of reptiles; Never very abundant or diverse. Greatest diversity of form in the Permian, Greatest success after the evolution of the shell in the Triassic
Anapsids
Carboniferous; Pelycosaurs in the early Permian, therapsids in the late Permian, True mammals in the Palaeocene
Synapsids
Carboniferous; Archosaurs, marine and flying reptiles in the Triassic. Dinosaurs in the Jurassic. Birds in the Palaeocene
Diapsids
from South Africa.
small, active insectivores of moderate size, with skulls typically around 5 cm long.
Permian Millerettids
lived in moderate to high southern latitudes.
were omnivores or herbivores.
Late Permian and Triassic Procolophonids
found in the northern hemisphere.
could reach 2-3m in length.
heavily build herbivores.
Late Permian Pareiasaurs
The first radiation was of the group known as
pelycosaurs.
the best-known pelycosaur.
Dimetrodon
radiated widely in the late Permian; shorter and more squat than the pelycosaurs.
Therapsids
common in the Triassic; include the species Thrinaxodon, which shows evidence of having had whiskers.
Cynodonts
suckle their young in pouches; found in South America and Australasia.
Marsupials
retain their young for longer inside the body; found in Asia, Europe, and N.A.
Placental mammals
lay eggs; found only in Australasia
Monotremes
humans, lemurs, monkeys, and apes, as well as our direct ancestors. Traced back to the late Cretaceous, radiated early Cenozoic.
Primates
Around 6 million years ago
grassland-dwelling apes were the
australopithecines.
oldest well-preserved skeletons; dated 3.2 million years ago.
evolved in two different ways:
1. towards heavily built vegetarians with small brains.
2. towards more lightly built omnivores who used simple tools
Australopithecus Afarensis
the more robust lineage
- identified in Africa.
- groups of these large vegetarians
likely coexisted with our direct ancestors.
Paranthropus
Australophithecus afarensis
Homo Habilis
Homo Erectus
Homo neanderthatensis
Homo sapiens
group including dinosaurs, birds, marine reptiles, modern reptiles, and pterosaurs.
DIAPSIDS
- successful group of diapsids.
- may have been warm-blooded.
- most archosaurs became extinct in the late Triassic
Archosaurs
the first flying vertebrates.
- ranged in size from a wingspan of a few centimeters to over 15 m.
- they were predominantly gliders and soarers;
- rarer species were adapted to other flying habits.
- must have been warm-blooded.
- coastal or marine predators.
- became extinct at the end of the Cretaceous.
Pterosaurs
Age of the Dinosaurs
Age of the Diapsids
Mesozoic
all theropods were predators, including Tyrannosaurus rex.
-appeared in the late Triassic and quickly evolved to alarge size, with species exceeding 9m in length by the early Jurassic.
Theropods
bird-hipped dinosaurs; also evolved from
therapods during the Jurassic.
- they were all herbivores.
- included armored forms such as Triceratops and the Stegosaurs, as well as the highly specialized
Iguanodonts and duck-billed dinosaurs
Ornithischians
evolved from theropods and shared with them the more primitive lizard-hipped pelvic pattern.
- they were vegetarians
- these are the group of dinosaurs that evolved to extremely large size, often over 20m in length and 50 tonnes in weight.
Sauropods
The reason for the extinction of the major diapsid groups
A catastrophic meteorite impact, probably on the Yucatan region of Mexico.
Igneous eruptions in India—responsible for significant climatic change.
from theropods during the Jurassic. An intermediate step, the primitive bird Archaeopteryx, is known from late Jurassic rocks of southern Germany.
Birds
are a group of large flightless birds that started to evolved early in the Cenozoic. They were once the top of predators of the early Cenozoic
Their descendents today include ostriches and emus.
Ratites
evolved in the Miocene. It may be that this was the time when birds evolved into a tree-dwelling habit and colonized dense woodland.
Perching song birds
lightly armored, jawed fish characterized by fins supported by a frontal spine.
Acanthodian
tool suite associated with Homo erectus
Acheulian
- ray-finned, bony fish, including most modern fish.
Actinopterygian
jawless fish.
Agnathan
primitive reptiles represented by modern turtles and tortoises. There are no holes in the skull behind the eye.
Anapsid
lower jaw bone in reptiles that articulates with the upper jaw, and an ear bone in mammals.
Articular
- group of fish characterized by a cartilaginous skeleton, represented by modern sharks and rays
Chondrichthyan
- early group of carnivorous mammals, now extinct.
Creodontids
mammal-like reptiles with many mammalian characteristics, including whiskers.
Cynodont
lower jaw bone of mammals and one of the lower jaw bones of reptiles.
Dentary
group including dinosaurs, birds, marine reptiles, modern reptiles, and pterosaurs, characterized by two skull apertures behind the eye
Diapsid
jawed fish
Gnathostome
group of species including Paranthropus, Austra-lopithecus, and Homo that includes our direct ancestors and no other living group
Hominid
- large, dorsal, blade-like bone of the pelvis.
Ilium
rear-facing bone of the pelvis.
Ischiurn
mammal that broods live young in a pouch
Marsupial
- large chewing muscle of mammals
Masseter
mammal that lays eggs.
Monotreme
tool suite associated with Neanderthal man
Mousterian
tool suite associated with Homo habilis.
Oldowan
bird-hipped dinosaurs.
Ornithischian
bony fish.
Osteichthyan
primitive group of mammal-like reptiles.
Pelycosaur
mammal that has a long gestation period and gives birth to large, live young.
Placental
heavily armored, jawed fish, common in the Devonian
Placoderm
forward-facing pelvic bone characteristic of bird- hipped dinosaurs.
Prepubic process
pelvic bone that faces forwards in lizard-hipped dinosaurs and backwards in bird-hipped dinosaurs.
Pubis
upper jaw bone of reptiles that articulates with the lower jaw, and an ear bone in mammals.
Quadrate
large, predatory flightless birds characteristic of the Palaeocene
Ratites
extinct group of lobe-finned fish that was probably the ancestor of tetrapods.
Rhipidistian
lobe-finned fish, including lungfish, coelocanths, and rhiphdistians
Sarcopterygian
large herbivorous dinosaurs.
Sauropod
division in mammalian skulls that allows
the animal to eat and breath at the same time.
Secondary palate
upper jaw bone that articulates with the lower jaw in mammals, but not in reptiles.
Squamosal
group including modern mammals and mammal-like reptiles, characterized by a single skull aperture behind the eye.
Therapsid - advanced group of mammal-like reptiles,
Synapsid
advanced group of mammal-like reptiles, specialized for temperate and high latitudes.
Therapsid
- carnivorous dinosaurs.
Theropod
