Marine Iguanas. Masturbation. Coercion.


When you're an 'alpha' male, you don't find it hard to mate with whichever lady you want. But when you don't have that high status, you still want to pass on your genes, right? So what do you do when you're a powerless 'beta'?

Background information:

Masturbation is just as common among many other animals as it is among humans. It's not just you. Marine iguanas (Amblyrhynchus cristatus) from the Galapagos Islands utilize it for something downright creepy!


It takes about 3 minutes of copulation for a male marine iguana to ejaculate. Three minutes too long for a weak 'beta' male that has invaded a stronger male's territory.

So, then, what does a weak male iguana do? He masturbates, stores sperm in little pouches near his hemipenis and then jumps on the female, sticks it in, impregnates her and feels proud of himself, although he shouldn't. This strategy was found to increase mating success for the 'betas' by 41%!

Luckily, it is not easy to get close to the females. 'Alphas' are much stronger than the 'betas', and they protect their territory. But those sneaky males have found a way around. The smaller, female-sized adult males do their best to make themselves look like females! That way they get really close, and their few seconds of luck are on.

Females marine iguanas are only sexually receptive for 24 days in January, so you can imagine that these guys need to be ready for action if they want offspring, or else they can wait for another year.


Photo credit: Gregory "Slobirdr" Smith

Common name:Marine iguana
Scientific name:Amblyrhynchus cristatus
Phylum:Chordata
Class:Reptilia
Order:Squamata
Family:Iguanidae
  
IUCN status:Vulnerable
Population trend:Unknown
Scientific reading: