L10 Bevan - Diving and Ecology

Question 1

Is it more effective to dive for a long period of time and reach anaerobic respiration, or to dive periodically and stay in aerobic respiration?

Answer 1

It is more efficient to dive at aerobic levels, rather than anaerobic.

If anaerobic respiration is used it takes significantly longer to recover, and is overall less efficient that if multiple aerobic dives are done

Question 2

What is more efficient?

a) short long dive
b) long deep dive with a gradual decent and ascent
c) short deep dives with a fast ascent and decent

Answer 2

a) is the most efficient, as if your prey is there then shallow dives are more efficient

out of b and c, b is more efficient as diving gradually is more efficient

Question 3

What did Thompson, Hibt and Fedak prove?

Answer 3

There is an optimum travel time

Question 4

How does O2 loading relate to diving animals?

Answer 4

If you use a lot of your O2, the regain is fast, but then plateaus off - the more O2 is loaded the harder it is to load - you can get away with 90%

Question 5

What action do diving animals take to use up myoglobin O2 stores?

Answer 5

stop blood supply to the muscles

Question 6

why do diving mammals normally dive within their cADL?

Answer 6

• anaerobic isn’t efficient

- they dive at a level that doesn’t produce lactic acid

Question 7

Diving birds routinely dive for longer than their cADL, why is this?

Answer 7

• may be due to a reduction in metabolic rate

- hypo metabolism brought on by hypothermia