Tristan Gooley

We all kind of know if you have one really hot day, it doesn't suddenly change everything around you.

Or if you have a cold snap, you're not expecting.

Things don't change by the hour.

But what the plants and animals are doing is counting something that's known as degree days.

So for every day the temperature is above a certain threshold, that counts.

So let's say it's five degrees above a line, then you have three days of it five degrees above a line.

The plants and animals count that as 15.

Whereas if it was eight degrees for three days, they count that as 24.

So it's amazing.

They've got this hidden abacus where they're counting the warmth over a period.

And so all the things we think of as seasonal will be tied to both the length of the day and night

and the cumulative change in temperature.

And each species is different.

It has its own gauge.

That's why some kind of like a small heat wave has a massive impact on small flying insects.

That's why we suddenly get a cloud of flying insects in front of us.

But it won't change, for example, the number of horses in a field.

Those animals are much more wedded to the length of day.

It's a good question.

And the way in, I think, is to think about reproduction strategies.