|
trait
|
Island syndrome
|
Reversed Island syndrome (RIS)
|
Trait changes mediated by increased POMC activity (the involved MCR is indicated)
|
|---|
|
Population density
|
high
|
Low or inconstant
|
-
|
|
Aggressiveness
|
low
|
high
|
high, MC5R
|
|
Body size
|
usually large
|
small in endotherms, either small or large in ectotherms
|
small, MC3-4Rs
|
|
Energy expenditure
|
low
|
high
|
high, MC3,4R
|
|
Sexual dimorphism
|
small
|
high
|
-
|
|
Development
|
-
|
faster, or anticipated
|
-
|
|
Voracity*
|
low
|
high
|
Either low or high, depending on the balance between MC3R and 4R
|
|
Pigmentation*
|
irrelevant
|
darker, but may occur in non-melanistic species as well
|
darker, MC1R
|
- Shifts in food intake rate and pigmentation (indicated with an asterisk) are not directly predicted by the RIS hypothesis and are only true if RIS is triggered by changes in melanocortin receptors activity, and these are not polymorphic. In the last column we report the trait shifts mediated by increase in POMC expression and their relationship with RIS.
