And not only do these genetic males mate with other males, they actually have the capacity to lay eggs even though they're genetic males.

Adult males a huge load.

We've separated the males from the females.

Adult males have large cheek flaps to show their dominance to other males.

Why throw out the male chicks?

Male will make long calls, both to attract females and advertise themselves to other males.

Positively amazing. Here's two males fighting.

Just like the male chicks.

The males have been put in little pots and the truck is going down the road and they are releasing males as they go.

In some species, infants are protected and transported by males in the group, particularly males who may be their fathers.

Adult male lions have a large mane.

Males and females differ in size and appearance.

There are few visible differences between males and females.

Old males may be almost pure white.

Males are larger than females and have a larger knob on their bill.

Females are considerably larger than males.

Females are generally smaller than males.

The size difference between males and females is proportionally greater in the larger tiger subspecies, with males weighing up to 1.7 times more than females.

And after that, the males all die. That's it for them.

I like them young, male, unmarried, slightly pissed off.

Why do they do that to the male calves?

Male octopuses die a few months after mating.

In the Asian species, only the males have large tusks.

The eyes are located above the chelicerae on the forward part of the prosoma.

Male okapis have short, skin covered horns called ossicones.

This will result in a more even ratio of males and females.

For most animals, males are the performers.

The earholes are on either side of the head, with no external pinnae.

Females are typically 10 20 smaller than males.

Male ligers are sterile, but female ligers are often fertile.

Males and females are similar in size and colouration.

The males are horned some females are horned, while others are polled.

Males may fight over mates underwater and on land.

For example, with howler monkeys both the males and females typically transfer from their natal group on reaching sexual maturity, resulting in groups in which neither the males nor females are typically related.

Male dogs are very serious about a hierarchy, because it prevents physical fights.

The larger males of a population tend to be more successful.

Males live for about a week, feeding on nectar and other sources of sugar.

It can also reduce its metabolism and heart rate and body temperature.

They also have a silver grey stripe that runs along the tail.

Juveniles are a mix of males and females (known as initial phase individuals), but the largest adults become territory holding (terminal phase) males.

These are squid. Now males, when they fight, if they're really aggressive, they turn white.

And so what you see here is two males who have had a fight.

Because all male chicks born in the egg industry are thrown out.

None of the other four male jaguars sighted in Arizona in the last 15 years have been seen since 2006.

When males do leave, they either live alone or with other males.