IRA FLATOW: And now, it’s time to play Good Thing, Bad Thing–

[MUSIC PLAYING]

–because every story has a flip side. Now, we’ve talked about the wild mustangs of the Western United States before, that are technically not wild. They’re a feral population of domesticated horses brought here by the Spanish almost 500 years ago.

And until recently, scientists believed the only true wild horses unimpacted by humans were the Przewalski horses in Central Asia. But in a surprising study published this week, scientists report that what we thought we knew about horse ancestry– well, it was wrong.

There are actually no more wild horses left anywhere on earth. Boy, if you’re a fan of horses, this is some really bad news, isn’t it? But is there a silver lining? Well, here to tell us the good and the bad of this new finding is Dr. Alan Outram, professor of archaeological science, University of Exeter. He joins us by Skype. Welcome to Science Friday.

ALAN OUTRAM: Hello.

IRA FLATOW: So you looked at the genome of the Przewalski horse. And what did you find? Who are they actually descendants of?

ALAN OUTRAM: Well, the earliest and ambiguous evidence for horse domestication comes from sites in Kazakhstan about 5,500 years ago. And those have never been sequenced before. So we sequenced quite a large number of ancient genomes from Botai, expecting them to be rather like modern domesticates, but actually found out that they are the direct ancestors of the Przewalski horse.

So they were under human management a long time in the past. So it’s actually not unlike the story you were telling a little bit earlier about the plants that Native Americans were farming in the past. They were wild, became domestic, and then went wild again. And the same applies to the Przewalski.

IRA FLATOW: So modern horses don’t come from the Botai, is what you’re saying, like we thought they did.

ALAN OUTRAM: No. That’s right. So, in fact, there must be– that’s the other interesting feature. There must be some sort of second domestication event elsewhere.

IRA FLATOW: So why is it so important that we have some wild horses left to study now? What makes them different from the feral horses out there?

ALAN OUTRAM: Well, I guess it is nice to be able to study something that has been impacted by humans to see what their natural behavior would have been like. It’ll help us understand how they acted in the very deep past. But, actually, nothing has actually gone extinct here in a way. The Przewalski horses are still alive. So it’s not like suddenly we’ve made a whole species extinct. It’s simply that they have been under human control at some point and now have gone back into being feral.

IRA FLATOW: So that’s the good news here then.

ALAN OUTRAM: Yeah. So, I mean, nothing is actually– I mean, before anybody gets really worried that an extinction has been caused by our paper this week, it hasn’t. These horses are still alive and well. And, still, their behavior is probably about as close to wild as we’re going to see, because they’ve been feral for a very long time.

IRA FLATOW: Right. So are these feral horses enough like the wild horses that we can still learn, study, learn from them?

ALAN OUTRAM: Well, I think we probably can still learn an awful lot from them. And they’re certainly the closest we now have. I suppose we can’t actually check that, because there are no other true wild horses to examine. But I would imagine that they’re the best thing that we can possibly still study. And they’re still incredibly important as a result of that.

IRA FLATOW: Do we know where the first modern horse comes from? Could it be– yeah.

ALAN OUTRAM: Well, that is the next phase of work that we have to work on. This is a continuing project, and we’re working on all other potential areas. The north area of Kazakhstan that we’d studied in the Botai culture. And it’s not the only candidate for, really, horse domestication.

There have always been other candidates, including the area of Ukraine and Russia to the west side of the Ural Mountains. And that is certainly an area we’ll be looking at, but they could also look at Eastern Anatolia and places like that.

IRA FLATOW: Sounds great. We’ll have you back on when you learn more about it, Dr. Outram. Thank you for taking time to be with us today.

ALAN OUTRAM: OK, thank you.

IRA FLATOW: Dr. Alan Outram, professor of archaeological science at the University of Exeter. Coming up, our buildings get taller and taller, but how exactly are engineers making it happen? We’re going to talk about the secrets of building immense structures.

Anything you ever wanted to know about building– now’s the time to get online and give us a call. Our number– 844-724-8255. We’re going to be talking with Roma Agrawal, structural engineer, author of Built– The Hidden Stories Behind our Structures. Give us a call– anything you’d like to know. We’ll be right back after this break.

Copyright © 2018 Science Friday Initiative. All rights reserved. Science Friday transcripts are produced on a tight deadline by 3Play Media. Fidelity to the original aired/published audio or video file might vary, and text might be updated or amended in the future. For the authoritative record of Science Friday’s programming, please visit the original aired/published recording. For terms of use and more information, visit our policies pages at http://www.sciencefriday.com/about/policies/