Social Behaviour- Aggression 9 Flashcards
When is there a peak in gonadal testosterone in red deer stags?
Just before the 2 week mating period which coincides with the highest incidence of aggression
What were the effects of castration on red deer stags (Lincoln et al.)?
Antlers were less developed, lost social status and there was no rutting behaviour
What happened when the castrated red deer stags were given testosterone?
Restored rutting behaviour and increased social rank
Antlers still did not fully develop
What hormone is important for non breeding aggression?
Oestrogens
What happens in mice if they are castrated before day 6 and then given testosterone later in life?
Showed male type aggression
Aggression is determined early in life in males
What was found in Syrian hamsters that suggests there is a second round of organisation around puberty?
Males castrated before puberty showed little aggression even when given testosterone
What happened when high anxiety rats were given a brain injection of oxytocin and AVP antagonists?
The high aggression was reduced
What is the challenge hypothesis?
Androgens are increased and associated with aggression only when intermale competition is high
If testosterone is advantageous why is it not produced all the time?
Foraging and survivorship reduced
Energy expenditure increased
