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500 million years ago, the world was a very different place.

The land was kind of boring and empty,

but the ocean was full of animals,

very different from the animals of today.

Vaguely beautiful and vaguely horrifying.

If you were in like a submarine or using like a deep sea rover, for example,

and you were looking at the animals there,

you would find animals that are able to eat each other,

animals that have the capacity to see, interact with their environment, swim, and burrow,

but the kinds of animals that are there are very different in terms of the proportion, like which groups are highly successful,

which groups have what kind of features, and many of them look vaguely familiar to the kind of animals you'd find in a modern ecosystem like in the ocean,

but also quite alien in some ways,

with different arrangements of their limbs and their eyes

and all sorts of like kind of interesting features that you know went extinct

hundreds of millions of years ago as well. This is Karma Nanglu, a postdoctoral

fellow at Harvard's Museum of Comparative Zoology and he spent a lot of time

studying this period, the Cambrian period.

500 million years ago, there were all these different life forms.

It was a total renaissance of biodiversity on Earth.

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