lecture 2 Flashcards
what is the Rostrum
describes the telescoping nose or beak of a cetatcean
what are key elements of a Cetatcean skull
- Lateral extension
- large and heavy mandibles
- vertebrae exit laterally
- skulls are porous and is filled with oils to help resonate vibrations, and affect buoyancy.
Are odontocetes skulls symmetrical or asymmetrical?
Asymmetrical with a single blowhole
Are Mysticete’s skulls symmetrical or asymmetrical?
symmetrical with two blowholes
What is the purpose of a melon?
It sends and directs signals that are used in echolocation to determine where prey may be
What is Baleen
- Found in mysticetes
- courseness determines type of feed
- acts as a filter
what is unique about the a whales vertebrae
Often fused in some or all parts
what is unique about whale bones?
they are light and spongy, best suited for low gravity of the ocean.
what is unique to only whales and manatees
vertically moving tale
describe a whales swimming technique thats different from fish
Whales appear to be galloping underwater, maybe due to there terrestrial origins.
why do whales evacuate their lungs when they dive
the oxygen they need is stored in their bloodstream. Air in the lungs would prevent them from diving.
what are the three layers of whale skin
epidermis, dermis, hypodermis
do whales have hair?
No, but a few hair follicles do appear sometimes
What is Homeothermy
the ability of a mammal to regulate a stable internal temperature.
how do whales keep maintain their body temperature?
Blubber
what are three benefits of blubber?
- keeps animal warm
- reserves energy for later
- streamlines the figure of the whale
what does encephalization quotient/Folding mean?
it is a measure of relative brain size of animals with different sizes
what does it mean when you say that a whale has “low encephalization”
the brain size of the whale is smaller than what is expected for its body size.
how do whales sleep?
it is hypothesized that whales are able to “shut off” one hemisphere of their brain to let it rest while being able to continue with its normal motor functions. This hypothesis is supported by a large “neuron highway” between the two hemispheres
