Mammals

Question 2

Mammal classification

Answer 2

Animalia, Chordata, Vertebrate, Mammalia

Question 3

Defining mammalian traits

Answer 3

• Mammalian gland - produce milk to feed youn
• Hair - protection, pigmentation and insulation
• Neaocrotex - advance parted of brain
• 3 middle ear bones
• Single lower jaw
• Complex Placenta (except monotremes and marsupials)
• Vivpacy (live young) (except Monotremes)
• Endothemy
• Four chambered hearts

Question 4

Evolutionary origins

Answer 4

• Evolved from Synapsid reptiles
• A small shrew-like mammal was first seen 225 mya
• 100 mya, masupial and placental mammals diversified

Question 5

Major groups

Answer 5

• Proteotheria - Oviparous, monotremes
• Metatheria - Viparous, pouch development and marsupials
• Eutheria - Viparous

Question 6

Diversity

Answer 6

• 6500 species
• 27 orders

Question 7

Monotremes

Answer 7

• Primitive
• Single-opening called a Cloaca
• Egg-laying
• No nipples
• Platypus, echnidaes
• Male platypus has venomous spur

Question 8

Marsupials

Answer 8

• Poorly developed young
• Young develop in pouch
• 7 orders (most in new guinea or australia)
• Convergent evolution

Question 9

Rodents (Rodentia)

Answer 9

• 1 pair of continously growing incisors in each jaw
• 2500 species

Question 10

Lagomorphs

Answer 10

• similar to rodents but has only 1 pair on incisors on upper jaw
• Double digestion, can digest a specialised faeces

Question 11

Primates

Answer 11

• Distinctive skelatal structure, opposable thumbs and large brains
• Highly intelligent, tool use
• Prosimians - monkeys, lesser apes, great apes
• Homidae - Gorillas, chimps, Orangatans, us

Question 12

Insectovoirs (Eulipotera)

Answer 12

• Small, ground-dwelling animal with pointed snout
• Insectovoires but may take on small vertebrates
• Shrews, moles, hedgehogs etc

Question 13

Bats (Chiroptera)

Answer 13

• Forelimbs form wegged wings, Flight!
• 2 main groups- large fruit bats and small echolating bats
• Highly diverse (1400 species)
• Disease vectors

Question 14

Carnivores (Carnivorae)

Answer 14

• Distinctive skull structure and defination
• Mostly meat eaters
• Diverse
• Often top predators

Question 15

Ungulates

Answer 15

• Hoofed mammals that walk on tiptoes
• Perissodactyla (odd toed) - horses, tapirs, rhinos
• Artiodactyla (even toed) - pigs, deer, hippos, sheep, goats, etc
• Herbivores

Question 16

Cetaceans (Cetacea)

Answer 16

• Forelimbs modified to flipped
• Vestigal hindlimbs
• Mainly marine, all aqautic
• Echolocation and electroception