Adaptive Physiology Flashcards
(28 cards)
2 ways to decrease density
1) increase lightweight materials (lung space, fat/blubber)
2) decrease heavy materials in body (bone density)
problems with being less dense
decreasing density makes diving more difficult
bottlenose dolphin solution to being less dense
oil in their bones
lungs role in diving
easily adjustable buoyancy controllers (MMs have large lung volume)
where can oxygen be stored other than lungs
- blood = increased blood volume and red blood cells
- muscles = increased capacity to store oxygen
what adaptation allows toothed cetaceans, wedded seals, and N. elephant seals to avoid the pressure when diving
hinged ribcage
warm blooded characteristics
1) generate heat internally when cold
2) cool down by sweating or panting
3) convert food to energy (heat)
4) eat more to produce energy
cold blooded traits
1) take on temp of enviro
2) body is hot in hot weather and vice versa
3) eat less for body mass
4) grow faster
ways to minimize heat loss
1) surface area to volume ratio (less surface area = less area to lose heat to enviro)
2) insulation (diff for diff species)
3) breathing (MMs breath less than humans)
types of insulation
1) hair
2) blubber
hair
- MMs that live on land and water rely on hair
- very dense (primary and under hairs)
- sebaceous glands (oil)
- naked/thinly covered areas which act as windows to dump heat
blubber
- most MMs
- thickness varies (individually and by species)
- total lipid (fat) content
- lots of vessels In blubber = control exposure to cooler water & act as heat sink during break exposure to warm water
- areas w/ little to no blubber to dump heat (thermal windows)
3 main purposes of skin
1) thermoregulation
2) drag reduction
3) buoyancy
counter current heat exchange
cold blood in veins is warmed by parallel pipes connected to arteries that contain warm blood
pharynx
- esophagus (food)
- larynx (air)
goose-beak
- echolocate, breathe, and swallow/eat at the same time
feeding
food supply not always consistent = better to be larger (more area to store food/fat/energy)
3 different feeding strategies
1) total herbivory
2) hunt single animals
3) engulf entire schools of fish/inverts
excretory system
MMs ingest more salt than terrestrial mammals = adapted kidney structure
- terrestrial mammals = 2 lobes
- MMs = multiple lobes
produce highly concentrated urine
- small bladders = frequent urination
only drink salt water in conditions of fasting
sexual maturity
females:
- size not age
- 85-95% of their mean adult body length (~5-12 yrs)
males:
- age
- 10-15 yrs
gestation
12 months (+/- 2 weeks)
inter-birth interval
~ 4-5 years
- due to high maternal investment
- conceive again w/in 9 months if calf dies (typically the 1st calf dies)
labor info
- ~20 min - 2.5 hours
- born tail first
- infanticide of ill/compromised calfs
calves
- 30-40 lbs & 3-4 ft
- dorsal fin flat
- fetal folds
- mom whistles constantly to acoustic imprint
- twins rare and usually unsuccessful
