Chapter 34 vertebrates Flashcards
Lateral line
The system which allows certain animals (such as sharks) to detect changes in water pressure and vibration
Convergent evolution
Two creatures evolving similar traits even though they are not related
Hominin
Humans and all of their ancestors
Hominid
All modern and extinct great apes
What are the four anatomical structures characteristic of chordates
Notochord
Acts as a skeleton, flexible rod between outside and gut
Dorsal Hollow nerve cord
Becomes the nervous system
Pharyngeal slits
Used for filter feeding by adults who retain this, or becomes other specialized parts in other animals
Muscular postanal tail
It is a tail, past the anus, creatures who retain this use it for underwater movement
What are the two chordate subphyla whose members lack backbones
Urochordates and cephalochordates
What additional specializations are seen in the vertebrates?
Highly cephalized, really developed sense organs, very distinct brain, backbone of vertebrae that protect the spinal cord, appendicular skeleton
Chondrichthyes
Cartilaginous fish
Osteichthyes
Bony fish
Actinopterygii
Ray finned fish (the fishiest fish)
Sarcopterygii
Lobe- finned fish (pendage like placement for fins)
Amphibia
Frogs, salamander, caecilians
Reptilia
All reptiles, including birds
Mammalia
Mammals
The members of which vertebrate groups are considered amniotes
Reptiles and mammals
Why was the development of the amniotic egg so important?
It allowed for vertebrates to move away from water
What are the four living orders of reptiles?
Crocodilians
Lizards and snakes (squamates)
Tuatara
Turtles
Are there really five living orders of reptiles? Explain
Yes there are, because birds are reptiles
What are the main characteristics of birds?
Feathers, only one ovary, no bladder, honeycomb shaped bones
What is the significance of Archaeopteryx?
It was the earliest bird we have ever found, 150 mya
What are the main characteristics of the class Mammalia?
Hair, mammary glands, (for the most part) don’t lay eggs, child develops inside of the mother, diaphragm, larger brains, varied teeth for different purposes
Monotremes
Still lay eggs
Platypus and echidnas
Marsupials
Birth happens very shortly after conception, stays in mothers pouch after birth
Kangaroo, opossum, koalas, etc.
Eutherian
Child fully develops inside the mother, connected to mother by placenta
Humans, tigers, elephants, etc.
List the characteristics of primates
Opposable thumbs, better shoulder joints, sensitive hands with flat nails, dexterous hands, eyes close together at front of face
What distinguishes the old world monkeys from the new world monkeys?
Old world: Nostrils face downward, generally live on the ground, no prehensile tail
New world: Nostrils open to the side, prehensile tail, primarily lived in trees
List the genera of apes.
Hylobates: gibbons
Pongo: orangutans
Gorilla: gorillas
Pan: Chimpanzees and bonobos
Homo: humans
What is meant by the term mosaic evolution?
Different traits which evolved separately for different purposes in one animal
What are two primary characteristics that distinguish humans from other primates?
Significantly larger brain size walking upright
What is the significance of the Australopithecus afarensis skeleton (Lucy)?
It is important because it might be our common ancestor to the australopithecine
What is the significance of Homo habilis? Homo ergaster? Homo erectus?
Homo habilis: they were the first to have simplified tools, and had larger brains than most primates
Homo ergaster: Had short and straight fingers for less tree swinging
Homo erectus: first ones to move out of Africa, taller with greater brain capacity, first ones to walk upright
Does Homo neanderthalensis represent a stage in the evolution of Homo sapiens?
No, they are more like our cousins
Where did Homo sapiens originate? How long ago?
We originated in Africa about 195 thousand years ago
