'I would like to know why man lions have manes and lady lions don't'

This is an article from Curious Kids, a series for children. The Conversation is asking kids to send in questions they’d like an expert to answer. All questions are welcome – serious, weird or wacky!

Bula! My name is Emelia and I am 6 years old. My little brother and I live in Fiji and we love listening to the Imagine This podcast! We love the episode about why cats don’t wear shoes. I would like to know why man lions have manes and lady lions don’t?– Emelia, age 6, Fiji.

Thank you, Emelia, for your very interesting question.

For a long time, people thought that boy lions had big shaggy manes to protect the area around their necks from being bitten or scratched during hunts and fights.

However, as time passed, scientists began to see that this idea didn’t really make sense.

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The first reason it didn’t make sense was that when lions fight each other, they don’t usually attack the neck at all. Instead, when they get into fights, they tend to bite along the back and hips. That means it is unlikely their neck would be close enough to another lion’s teeth to get bitten. So it wouldn’t make much sense for the mane to protect a place that wasn’t in danger.

Another big reason that people no longer think that manes are there to protect boy lions is because of the way lions hunt. When looking for food, lions hunt in a group called a pride. But both boy lions and girl lions in the pride work together when they hunt. So if manes were supposed to be for protection, then why wouldn’t girl lions and boy lions both have manes?

So because scientists found that their old ideas couldn’t be true, they came up with new possibilities that would fit with what they were seeing. This happens all the time in science.

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Instead of being for protection, people now think that the boy lion’s mane shows the girl lions how healthy and strong he is. The idea is that the stronger and healthier a boy lion looks, the better the girl lion’s babies will grow since they would have a dad with good genes. (Genes are the “recipe” that tells a baby animal or plant how to grow, so having parents who are strong and healthy makes you more likely to grow up strong and healthy.)

Some studies show that female lions even prefer darker coloured manes to bigger manes. A pale mane might mean the lion is experiencing stress – for example, they might not be getting enough of the right foods or they might be feeling sick. The dark colour seems to show that the boy lion is under less stress.

In the same way that dark clothes make us hotter than white clothes would, the dark mane shows that the lion can do well in hot weather.

This is really important in the warm climates where lions live.

Lions aren’t the only animals that choose their mates based on how they look. For instance, girl peahens tend to like boy peacocks with the biggest and showiest feather displays.

So scientists now think that a lion’s big puffy mane probably isn’t there for protection.

Instead, we think the mane, and especially its colour, helps the boy lions show the girl lions how healthy and strong they are. Then the girl lions will know who will be a good dad for her babies.

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