This is fresh air, I'm Terry Gross. After reporting on the first year of the pandemic for the Atlantic,

for which he want to pull its surprise, my guest, science writer Ed Young, decided he needed to take a

break. He wanted to shift his focus from the catastrophes and tragedies caused by COVID.

To a facet of the natural world, he hoped would bring some joy to his life and to his readers.

The result is his new book, An immense World, How Animal Senses Reveal the Hidden Realms Around Us.

It's almost like science fiction or the supernatural and that it describes the world that animals, birds,

and insects perceive that humans can't. The sound smells, colors, vibrations, echoes,

and magnetic fields that exist beyond the limits of our senses. He writes about animals with eyes on

their genitals, ears on their knees, noses on their limbs, and tongues all over their skin. Some

sensations that people perceive as pain aren't experienced as pain in certain species. As he puts it,

every animal, including humans, can only tap into a small fraction of reality's fullness.

The book is about the diversity of perception in the animal world and the limitations of our own

perception. Ed Young wrote about sensory biology before the pandemic and is now back to writing about

COVID. We'll get to that later. Ed Young, welcome back to Fresh Air. Hi, thanks for having me.

So your book is about how every animal, including us, isn't closed within its own sensory bubble.

As you put it, perceiving but a tiny sliver of an immense world, which leads to the world

word, um-well, which is a word I'm sure you'll be using. So why don't you describe what it is?

So, Umfelt was popularized by a German biologist named Jacob van Uckschull. The word comes from

the German for environment, but van Uckschull wasn't using it to mean the physical environment.

He meant the sensory environment, the unique set of smells, sights, sounds and textures

that each animal has access to. And that might be unique to it. It's own little bespoke sliver

of reality. So I'll give you an example. Humans can see colours ranging from red to violet, but we

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