Lecture's 22-29 Flashcards
What are the characteristics of Birds?
10,000 species;
Reduced organs such as no bladder and 1 ovary;
Feathers for flight;
Large pectoral muscles for strength to fly
Why were early birds flightless but had feathers
Feathers initially evolved for another function
What characteristic do mammals and retiles share
amniotic eggs
3 major lineages of mammals
Monotremes, Marsupials, Eutherians
Name the derived traits of mammals
-Mammary glands
-Hair
-Fat layer under skin
-Endotherms
-Larger brains
-Extended parental care
-Diverse teeth
Monotremes
platypus
- Lay eggs
- Mammary glands but lack nipples
Marsupials
Opossums, kangaroos, koalas
- complete embryonic development outside the uterus while nursing
- early development in uterus, includes a placenta
Eutherian characteristics
-More complex placentas
- Lack epipubic bone which allows for expansion of pregnancy
- Longer pregnancy
- Developed completely in uterus
Types of Eutherians
Rodents, Humans, Ungulates (hooved animals), Cetaceans
Cetaceans
land mammals that returned to water. Vestigial hindlimbs
- Blue whales
Derived traits of primates
- Hands and feet adapted for grasping
- Flat nails instead of claws
- Large brain, short jaws
- Eyes look forward - hand/eye coordination
- Flexible opposable thumb
Primate lineages
Apes diverged from Old World monkeys
Traits of Hominins
- Upright and bipedal
- Larger brain, complex thought, tool use
- reduced jawbones and teeth
- shorter digestive tract
Traits of Australopiths
- 4-2 MYA
- FULLY erect
- Small brain
- Human- like hands and feet
- Lucy
Traits of Homo Habilis
- 2.4-1.6 MYA
- Shorter jaw
- Larger brain
- Used tools
Traits of Homo Ergaster
- 2-1 MYA
- Larger brain
- No more tree climbing
- Smaller teeth
Traits of Homo Erectus
- 1.8 MYA - 200,000 YA
- Taller (5-6 ft)
- Used fire to cook food
- Migrated out of Africa
Traits of Hedidelbergensis
- 700,000- 200,000 YA
- First species to live in exclusively colder climates
- Built shelters
Traits of Neanderthals
- 400,000- 40,000 YA
- Europe spread to Asia
- Short, stocky bodies adaptions the environment
- Made complex tools
- Buried their dead
- Divereged from Homo Sapiens
Hyperosmosis
water in organism < water in environment
- water moves IN, salt moves OUT
Hypoosmosis
water in organism > water in environment
- water moves OUT, salt moves IN
Isosmosis
water in organism = water in environment
- water, salts continuously diffuse
