Chapter 34. Vertebrates. Vertebrates. Get their name from vertebrae, the series of bones that make up the backbone. Vertebrates. There are approximately 52,000 species of vertebrates
Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.
Get their name from vertebrae, the series of bones that make up the backbone
Echinodermata(sister group to chordates)
Chondrichthyes(sharks, rays, chimaeras)
Reptilia(turtles, snakes,crocodiles, birds)
Lungs or lung derivatives
Jaws, mineralized skeleton
Ancestral deuterostomeA hypothetical phylogeny of chordates
Pharyngealslits or clefts
Muscular,post-anal tailDerived Characters of Chordates
2. Dorsal, hollow nerve cord
4. Muscular post-anal tail
Dorsal, hollownerve cord
Pharynx with slits
(b) In the adult, prominent pharyngeal slits function in suspension feeding, but other chordate characters are not obvious.
(a) An adult tunicate, or sea squirt, is a sessile animal (photo is approximately life-sized).
(c) A tunicate larva is a free-swimming butnonfeeding “tadpole” in which all fourchief characters of chordates are evident.Tunicates (subphylum Urochordata)
Dorsal, hollownerve cord
TailLancelets (subphylum Cephalochordata)
Dorsal edgesof neural plate
(a) The neural crest consists of bilateral bands of cells near the margins of the embryonic folds that form the neural tube.
(b) Neural crest cells migrate todistant sites in the embryo.
Migrating neuralcrest cells
(c) The cells give rise to some of the anatomical structuresunique to vertebrates, including some of the bones and cartilage of the skull.Neural crest cells
(a)Haikouella. Discovered in 1999 in southern China, Haikouella had eyes and a brain but lacked a skull, a derived trait of craniates.
(b) Haikouichthys.Haikouichthys had a skull and thus is considered a true craniate.The Origin of Craniates
In other Cambrian rocks paleontologists have found fossils of even more advanced chordates, such as Haikouichthys
Dorsal viewof head
DentalelementsFossils of Early Vertebrates
Blacktip reef shark (Carcharhinus melanopterus).Fast swimmers with acute senses, sharks have paired pectoral and pelvic fins.
Southern stingray (Dasyatis americana).Most rays are flattened bottom-dwellers thatcrush molluscs and crustaceans for food. Some rays cruise in open water and scoop food into their gaping mouth.Sharks and Rays
Spotted ratfish(Hydrolagus colliei). Ratfishes, typically live at depths greaterthan 80 m and feed on shrimps, molluscs, and sea urchins. Some species have a poisonous spine at the front of their dorsal fin.Ratfish
Adipose fin(characteristic oftrout)
Cut edge of operculum
Pelvic finFish anatomy
(a) Yellowfin tuna (Thunnus albacares), a fast-swimming, schooling fish that is an important commercial fish worldwide
(b) Clownfish (Amphiprion ocellaris), a mutualistic symbiont of sea anemones
(c) Sea horse (Hippocampus ramulosus), unusual in the animal kingdom in that the male carries the young during their embryonic development
(d) Fine-spotted moray eel (Gymnothorax dovii), a predator that ambushes prey from crevices in its coral reef habitatRay-Finned Fishes (Class Actinopterygii)
Includes nearly all the familiar aquatic osteichthyans.
The fins, supported by long, flexible rays are modified for maneuvering, defense, and other functions.
TetrapodlimbskeletonThe Origin of Tetrapods
AmniotesOrigin of Tetrapods
With a fishlike
tail and internal
The male grasps the female, stimulating her to release eggs. The eggs are laid and fertilized in water. They have a jelly coat but lack a shell and would desiccate in air.
During metamorphosis, the gills and tail are resorbed, andwalking legs develop.Amphibians
Order Urodela. Urodeles (salamanders) retain their tail as adults.Order Urodela
Order Anura. Anurans, such as this poison arrow frog, lack a tail as adults.Order Anura
Order Apoda. Apodans, or caecilians, are legless, mainly burrowing amphibians.Order Apoda
AncestralamnioteA phylogeny of amniotes
Traditionally, lizards, snakes, and crocs are classified together in the Class Reptilia with birds in a separate class (Aves)
But crocodiles may actually be more closely related to birds than to lizards and snakes
Chorion. together in the Class Reptilia with birds in a separate class (Aves) The chorion and the membrane of the allantois exchange gases between the embryo and the air. Oxygen and carbon dioxide diffuse freely across the shell.
Allantois. The allantois is a disposal
sac for certain metabolic wastes pro-
duced by the embryo. The membrane
of the allantois also functions with
the chorion as a respiratory organ.
Yolk sac. The yolk sac contains the yolk, a stockpile of nutrients. Blood vessels in the yolk sac membrane transport nutrients from the yolk into the embryo. Other nutrients are stored in the albumen (“egg white”).
Amnion. The amnion protectsthe embryo in a fluid-filled cavity that cushions againstmechanical shock.
Amniotic cavitywith amniotic fluid
ShellThe extraembryonic membranes
Hatching Komodo dragon
Deinonychus together in the Class Reptilia with birds in a separate class (Aves)Dinosaurs
Diversified into a vast range of shapes and sizes
Included the long-necked giants called the theropods
Nesting Oviraptor and eggs
Tuatara together in the Class Reptilia with birds in a separate class (Aves)(Sphenodon punctatus)Lepidosaurs
Found only in New Zealand…endangered
Australian thorny devil lizard together in the Class Reptilia with birds in a separate class (Aves)(Moloch horridus)Squamates
Wagler’s pit viper together in the Class Reptilia with birds in a separate class (Aves)(Tropidolaemus wagleri)Snakes
Eastern box turtle together in the Class Reptilia with birds in a separate class (Aves)(Terrapene carolina carolina)Turtles
American alligator together in the Class Reptilia with birds in a separate class (Aves)(Alligator mississipiensis)Alligators and Crocodiles
Finger 1 together in the Class Reptilia with birds in a separate class (Aves)
(b) Bone structure
(c) Feather structureBirds
Wing claw together in the Class Reptilia with birds in a separate class (Aves)
Airfoil wing with contour feathers
Long tail with many vertebraeThe Origin of Birds
Emu. together in the Class Reptilia with birds in a separate class (Aves) This ratite lives in Australia.The ratites, order Struthioniformes
Mallards. together in the Class Reptilia with birds in a separate class (Aves) Like many bird species, the mallard exhibits pronounced color differences between the sexes.
Laysan albatrosses. Like most birds, Laysan albatrosses have specific mating behaviors, such as this courtship ritual.
Barn swallows. The barn swallow is a member of the order Passeriformes. Species in this order are called perching birds because the toes of their feet can lock around a branch or wire, enabling the bird to rest in place for long periods.Flying birds
Raptor together in the Class Reptilia with birds in a separate class (Aves)(such as a bald eagle)
Grasping bird (such as a woodpecker)
Swimming bird(such as a duck)
Perching bird (such as a cardinal)Foot Structure
Jaw joint together in the Class Reptilia with birds in a separate class (Aves)
(a) The lower jaw of Dimetrodon is composed of several fused bones; two small bones, the quadrate and articular, form part of the jaw joint. In Morganucodon, the lower jaw is reduced to a single bone, the dentary, and the location of the jaw joint has shifted.
Incus (evolvedfrom quadrate)
Malleus (evolvedfrom articular)
(b) During the evolutionary remodeling of the mammalian skull, the quadrate and articular bones became incorporated into the middle ear as two of the three bones that transmit sound from the eardrum to the inner ear. The steps in this evolutionary remodeling are evident in a succession of fossils.Early Evolution of Mammals
Are a small group of egg-laying mammals consisting of echidnas and the platypus
A young brushtail possum. together in the Class Reptilia with birds in a separate class (Aves) The young of marsupials are born very early in their development. They finish their growth while nursing from a nipple (in their mother’s pouch in most species).Marsupials
Long-nosed bandicoot. together in the Class Reptilia with birds in a separate class (Aves) Most bandicoots are diggers and burrowers that eat mainly insects but also some small vertebrates andplant material. Their rear-opening pouch helps protect the young from dirt as the mother digs. Other marsupials, such as kangaroos, have a pouch that opens to the front.Marsupials
Marsupial mammals together in the Class Reptilia with birds in a separate class (Aves)
This clade of eutherians evolved together in the Class Reptilia with birds in a separate class (Aves)in Africa when the continent was isolated from other landmasses. It includesEarth’s largest living land animal (the African elephant), as well as species that weighless than 10 g.
This diverse clade includes terrestrial and marine mammals as well as bats,the only flying mammals. A growingbody of evidence, including Eocene fossils of whales with feet,supports putting whales inthe same order (Cetartiodactyla)
as pigs, cows, and hippos.
This is the largest eutherian clade. It includes the rodents, which make up the largest mammalian order by far, with about 1,770 species. Humansbelong to the order Primates.
All members of this clade, which underwent an adaptive radiation in South America, belong to the order Xenarthra. One species, the nine-banded armadillo, is found in the southern United States.
Afrosoricida (golden moles and tenrecs)
Macroscelidea (elephant shrews)
Dermoptera (flying lemurs)
Scandentia (tree shrews)
Possible phylogenetic tree of mammals.All 20 extant orders of mammals are listed at the top of the tree. Boldfaced orders are explored on the facing page.
Ancestral mammalPhylogenetic relationships of mammals
MAIN together in the Class Reptilia with birds in a separate class (Aves)CHARACTERISTICS
Embryo completes development in pouch on mother
Lay eggs; nonipples; young suck milk fromfur of mother
Teeth consisting of many thin tubes cemented together; eats ants and termites
Long, musculartrunk; thick, loose skin; upper incisors elongated as tusks
Short legs; stumpy tail; herbivorous; complex, multichambered
Aquatic; finlikeforelimbs and no hind limbs; herbivorous
Chisel-like, continuously growing incisors worn down by gnawing;herbivorous
Reduced teeth orno teeth; herbivorous(sloths) or carnivorous (anteaters, armadillos)
Opposable thumbs; forward-facing eyes; well-developed cerebral cortex; omnivorous
Lagomorpha Rabbits, hares, picas
Chisel-like incisors; hind legs longer than forelegs and adapted for running and jumping
Golden lion tamarin
Hooves with an odd number of toeson each foot; herbivorous
Sharp, pointed canineteeth and molars for shearing; carnivorous
CarnivoraDogs, wolves,bears, cats, weasels, otters,
Adapted for flight; broad skinfold that extends from elongated fingers to body and legs; carnivorous or herbivorous
Hooves with an even number of toes on each foot; herbivorous
CetartiodactylaArtiodactylsSheep, pigs cattle, deer,giraffes
Aquatic; streamlinedbody; paddle-like forelimbs and no hind limbs; thicklayer of insulating blubber; carnivorous
Diet consists mainly of insects and other small invertebrates
Pacific white-sided porpoiseThe major eutherian orders
Anthropoids together in the Class Reptilia with birds in a separate class (Aves)
Old World monkeys
New World monkeys
Lemurs, lorises, and pottos
Millions of years ago
60The Primate Family Tree
(a) together in the Class Reptilia with birds in a separate class (Aves) New World monkeys, such as spider monkeys (shown here), squirrel monkeys, and capuchins, have a prehensile tail and nostrils that open to the sides.
(b) Old World monkeys lack a prehensile tail, and their nostrils open downward. This group includes macaques (shown here), mandrills, baboons, and rhesus monkeys.Monkeys
(a) together in the Class Reptilia with birds in a separate class (Aves) Gibbons, such as this Muller's gibbon, are found only in southeastern Asia. Their very long arms and fingers are adaptations for brachiation.
(b) Orangutans are shy, solitary apes that live in the rain forests of Sumatra and Borneo. They spend most of their time in trees; note the foot adapted for grasping and the opposable thumb.
(c) Gorillas are the largest apes: some males are almost 2 m tall and weigh about 200 kg. Found only in Africa, these herbivores usually live in groups of up to about 20 individuals.
(e) Bonobos are closely related to chimpanzees but are smaller. They survive today only in the African nation of Congo.
(d) Chimpanzees live in tropical Africa. They feed and sleep in trees but also spend a great deal of time on the ground. Chimpanzees are intelligent, communicative, and social.Hominoids
Paranthropus together in the Class Reptilia with birds in a separate class (Aves)robustus
Millions of years ago
(b) together in the Class Reptilia with birds in a separate class (Aves) The Laetoli footprints, more than 3.5 million years old, confirm that upright posture evolved quite early in hominid history.
(a) Lucy, a 3.24-million-year-old skeleton, represents the hominid species Australopithecus afarensis.
(c) An artist’s reconstruction of what A. afarensis may have looked like.Australopiths