But even other species tend to have adorable infants.

So, why has science conditioned us to find babies so precious?

Is there something specific that triggers our urge to hold and squeeze them?

Interestingly, studies have found that macaque monkeys pay little attention to newborn faces, leading researchers to believe that the cute feeling may be an entirely human trait.

Unlike many other species, once born, human babies are completely dependent on their parents for survival.

As a result, humans have adapted to find certain traits aesthetically pleasing and downright adorable in an effort to increase interaction, care and protection from parents.

This, in turn, enhances offspring survival and perpetuates our species.

But what exactly makes something seem cute?

Known as "baby schema", scientists have come up with a set of tested traits that make something appear cute.

These include a large rounded head, relative to the body, large eyes below the mid-line of the face, protruding cheeks, a big forehead, round body, and soft surfaces.

Awwww!

And, no doubt, our species is born with fully grown large eyes, almost full-sized brains, soft skin, big cheeks, and round bodies.

In fact, in tests where baby photos are manipulated to have more baby schema traits, whether they're human babies or dogs and cats, for example, they're rated as cuter and participants felt a stronger motivation to take care of these babies.

Even when the front of cars were altered in accordance to the baby schema, like, making the headlights become larger to mimic big eyes, participants experienced a more positive response.

It turns out it's all in our head!

When viewing babies with enhanced baby schema proportions, the mesocorticolimbic system of our brain is activated.

These parts of the brain enhance the anticipation of a reward, and can lead to a sense of enjoyment and motivation to care for something and the urge to cuddle or hold an object.

But what about things that aren't...so cute?

In fact, some creatures are downright ugly!

So, what does science have to say about these?

Our friends at "Earth Unplugged" have answered this very question in our collaboration on animals.

So, click on the screen or on the link in the description to find out.

Huge thanks to the team at Earth Unplugged for providing us with all this footage.

Go watch their video and follow them for even more amazing content.

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