Mammal Charateristics & Classification
do all mammals give live birth?
NO, while most mammals give live birth, platypus lay soft shelled eggs
BUT they all give milk :)
do toothed whales or baleen whales echolocate? DAILY DOUBLE: what are their distinct subcategories
Toothed whales ONLY
Mysticeti = baleen, Odontoceti = toothed
What are two types of Sirenians?
Manatees & dugongs
What visible structures do sea lions have that seals lack?
External ear flaps, Pinniped (front flippers) that improve their locomotion on land
Bonus + 100 forward turning hind limbs
Why does sound travel faster in water than in air?
Water molecules are closer together than gas molecules, which allow sound particles to travel faster from molecule to molecule
What characteristic allows mammals to maintain a constant internal body temperature?
Endothermy/Thermoregulation
1/2 points for blubber and thick fur
What process do toothed whales use to locate prey and navigate?
Echolocation
What is the primary diet of Sirenians?
Seagrass/plants (only marine mammals that are fully herbivorous)
What structures do walruses use for social dominance and maneuvering on ice?
Tusks
Name 2 natural sources of ocean noise.
Lighting, earthquake, underwater volcano, ice cracking, whale songs, oyster toadfish, plus more
True or False: mammals have exoskeletons, not endoskeletons
What material is baleen made from?
Keratin
True or False: Sea otters are keystone species that control sea urchin populations.
extra point: what order of animal are sea otters in?
True. Carnivora, Fissipeds
What pinniped family includes the true seals?
Phocidae
Name TWO human activities that contribute to ocean noise pollution.
answers include ships, tankers, sonar, oil exploration, construction, dredging
What order includes seals, sea lions, and walruses?
Carnivora
What structures expand in lunge-feeding whales?
Ventral grooves
how does the hollow hair of polar bears help them keep warm? (hint: has to do w/ the color of their skin)
what is the beneficial bacteria on seals teeth? (1/2 points) what color does it make their teeth ?
chromogenic bacteria, makes their teeth black
how does sound vibrations play into echolocation;what body part do they interact with?
toothed whales have no external ear canals. Instead, they receive returning echoes through acoustic fat in the lower jaw
Clicks are focused into a narrow beam through the melon, a fatty organ on the forehead that acts like an acoustic lens, refracting and directing the sound forward (lower jaw/melon accepted)
Name THREE characteristics shared by mammals.
Answers include hair, mammary glands, endothermy, lungs/air breathing, 4-chambered heart, large complex brain
What fatty structure helps focus outgoing sound waves during echolocation?
Melon
4 days at a time
what seal species has countershading coloration?
ringed seal
(half points for naming other species that have countershading: orca, penguin)
how do whales make clicks?
toothed whales produce high‑pitched clicks by forcing pressurized air through phonic lips, two tissue structures in the nasal passage just below the blowhole