Chapter 34 Flashcards
series of bones that make up the backbone
vertebrae
Presently about ___ species of vertebrates
52,000
provides skeletal support
notochord
adult retains only ___ of embryonic notochord
remnants
The dorsal, hollow nerve cord, evolved into the central nervous system which contains?
brain and spinal cord
The pharyngeal slits, or clefts, evolved into?
parts of ear, head, and neck in tetrapods
Similarity in developmental genes between today’s ___ ___ and ___.
invertebrate chordates; vertebrae
are chordates with a backbone
Vertebrates
four limbs, and feet with digits
ears for detecting airborne sound
early ones remained dependent on water (shared with today’s amphibians)
derived characteristics of tetrapods
Next important step in evolution?
evolution of amniote egg
contains membranes that protect embryo from environment
amniote egg
What are the different types of reptiles?
lizards, snakes, turtles, crocodilians, birds, and the extinct dinosaurs
Almost every feature of what kind of anatomy is modified for flight?
reptile
Birds descended from small, carnivorous dinosaurs approximately ___ ___ years ago.
150 million
oldest bird known
archaeopteryx
amniotes that produce milk in mammary glands for offspring
mammals
hair and layer of fat to retain body heat
efficient respiratory and circulatory systems
larger brain than other vertebrates of equivalent size
mammals
What are today’s 3 living lineages? (mammal)
- Monotremes
- Marsupials
- Eutherians
small group of egg laying mammals
monotremes eg. echnida and platypus
embryo develops within a placenta in mother’s uterus
marsupials eg. kangaroo, opposum
embryonic development completed within uterus, joined to mother by the placenta
longer pregnancy
eutherians (placental mammals) eg. cats, dogs, whales, primates
forward-looking eyes close together on face=
depth perception in primates
Compared to other apes, humans have what?
- upright posture and bipedal locomotion
- larger brains
- language capabilities and symbolic thought
- can manufacture and use complex tools
The species Homo sapiens is about ___ years old.
200,000
Fossils have been found in Africa of species more closely related to humans than to chimpanzees. What are they known as and how long ago?
Hominins; 6.5 million years ago
The species Homo originated when?
2.5 million years ago
The first hominin to leave Africa was ___ ___ who originated in Africa ___ ___ years ago.
Homo erectus; 1.8 million years ago
Homo sapiens appeared in Africa when?
195,000 years ago
Humans first arrived in the New World sometime before?
15,000 years ago
lived in Europe and the Near East from 200,000 to 28,000 years ago
Homo neanderthalenis
