Endothermy And Feeding

Question 1

How does the BMR of endothermic compare to that of ectotherms?

Answer 1

7-10 times higher BMR

Question 2

What is BMR?

Answer 2

Metabolic activity during minimal resting lifestyle with no spontaneous activity/digestion or stress

Question 3

Endotherms body heat

Answer 3

28 to 42 degrees and constant (+/-2 degrees)

Question 4

What is Bergmann’s rule 1987?

Answer 4

Ecogeographical rule that states that species of larger size are found in colder climates and species of smaller size are found in warmer climates

Question 5

Insulation

Answer 5

Layers of fat (blubber) provide insulation however any land activity with this can lead to overheating

Question 6

What is counter current heat exchange?

Answer 6

Heat loss via the flow of warm blood to cool blood due to a specific arrangement of the blood vessels

Question 7

Heterothermy

Answer 7

Self regulation of internal body temperature and allowance of surrounding environment to affect it

Question 8

Allen’s rule 1877

Answer 8

Mammals and birds living in colder climates have shorter appendages than those of warmer climates

Question 9

Gloger’s rule 1833

Answer 9

‘’Races in warm and humid areas are more heavily pigmented than this in cool and dry areas’’

Question 10

Winter survival mechanisms (5)

Answer 10

DBATH
Dormancy
Body mass (reduction)
Activity (reduction)
Torpor
Hibernation (extreme torpor)

Question 11

Examples of behavioural adaptions to heat (2)

Answer 11

Majority nocturnal activity which avoids exposure to high temperatures
Burrows and night to provide patches of shade in the day

Question 12

How is the brain kept cool?

Answer 12

Specific anatomical arrangement that promotes cooling

Question 13

What are the two hypotheses for the evolution of endothermy?

Answer 13

1. Nocturnalisation (Crompton, 1978)

2. Aerobic capacity (Bennet and Ruben, 1979)

Question 14

X

Answer 14

X

Question 15

X

Answer 15

X