Flashcards in Lecture 34 - Vertebrates II (Mammals) Deck (32)
4 Derived Characteristics of Mammals
1. Differentiated teeth
3. Mammary glands
4. Proportionately large brain
What are the 3 living lineages of mammals?
Marsupials definition (EX:)
-embryo develops within placenta of mother’s uterus
-completed development in mother’s pouch (EX: kangaroo)
Monotremes definition (EX)
-egg-laying mammals (EX: platypus)
Eutherians definition (EX)
-most diverse mammalian group
-young complete development in uterus + born more developed
-EX: bats, carnivores, rodents etc.
what are 3 basic eutherian characteristics?
1. Known as placenta mammals
2. Complete embryonic development in uterus, joined to mother more complex placenta with much more developed young at birth
3. 65 million year ancestor rodent-like animal
Chiroptera (defining characteristic)
only mammals that have evolved true flight
diverse ecology: feed on insect, nectar, fruit etc.
What caused Ebola?
manatees and dugongs
Sirenia (defining characteristic)
Only herbivore marine animals
Which species of Sirenia is extinct?
steller's sea cow
Sirenia (3 characteristics)
-live in tropic areas
toothed whales (orcas, dolphins)
baleen whales (largest animals that have ever lived)
Which Cetacea is extinct?
Yangtze river dolphin functionally extinct since 1990s
3 characteristics of Cetacea
1. Ancestors of modern whales were land mammals
2. Common ancestor with hippos
3. Many at risk or recovering species
What is a common California whale?
(zebras, mules, horses etc)
2 characteristics of Perissodactyla
1. Odd-toed herbivores
2. Rhinos going extinct due to habitat exploitation + poaching
-Javan rhinos extinct in Vietnam
hoofed animals EX: sheep, giraffes, antelope, pigs, deer, cattle etc.
2 characteristics of Artiodactyla
1. Even-toed ungulates (carry weight on 3rd and 4th toe)
2. Herbivorous economically important
2 characteristics of Rodentia
1. Incisors that grow constantly
2. Make up ½ of mammal species
dogs, cats, bears, weasels
3 characteristics of Carnivora
2. 280 species with many in decline
3. bag cats decreasing very quickly