IRA FLATOW, host:
This is TALK OF THE NATION: SCIENCE FRIDAY. I'm Ira Flatow.
When you picture a penguin - now, you see it's surrounded by snow and ice, right? Braving that brutal polar wind to shield a single egg until it hatches -I know you've seen the movie. But not all penguins were built for the cold. And this week, scientists are reporting that they have found at least two new species and possibly one - as many as five species that once lived in the warm desert of what is now Peru, millions of years earlier than once thought, and one of them was five feet tall.
Joining me now to talk more about the new find is my guest, Julia Clarke, assistant professor in the Department of Marine, Earth and Atmospheric Sciences at North Carolina State University in Raleigh. She's also research curator of paleontology at the North Carolina Museum of Natural Sciences and a research associate at the American Museum of Natural History here in New York. Welcome to SCIENCE FRIDAY.
Professor JULIA CLARKE (Department of Marine, Earth and Atmospheric Sciences Assistant Professor, North Carolina State University): Oh, thank you for having me.
FLATOW: Were you surprised yourself at this discovery?
Prof. CLARKE: Oh, absolutely. You know, and just the age of these new discoveries and the giant size of our 36 million-year-old species. It's really quite striking.
FLATOW: So set the scene for us. Before these find in Peru, what do we know or think we knew about where penguins have lived in the past?
Prof. CLARKE: Well, there had been a consensus that penguins originated in the very southern high latitude region. And it only reached low latitude equatorial regions much less than 50 million years ago, perhaps as recently as four million years ago.
FLATOW: So they went from the south to the equator?
Prof. CLARKE: Yes, exactly. And we thought that although, you know, we know that the earliest fossil penguin is around 61 million years - that's only four million years after the extinction of the non-avian dinosaurs in high latitude New Zealand - we thought that they only made their way to these equatorial regions very, very recently.
FLATOW: And this now upsets that card.
Prof. CLARKE: Absolutely. And the question isn't simply, you know, just pushing it back a lot further in Earth's history. It's a very different - the Earth is a very different place when we now know that these species arrived at these equatorial regions. You know, we previously thought that only close relatives of living species of penguins - and living species reached these equatorial regions during a much cooler Earth, an Earth with ice caps and overall much, much cooler than it was when these new species lived about 36 and 42 million years ago.
FLATOW: Mm-hmm. So these species that you discovered are able - were able to live in a warmer climate?
Prof. CLARKE: Absolutely. And what we find is that in fact is striking, with our new data and data published last year, is that penguins really flourished early in our history in these much warmer conditions. These are conditions where equatorial regions and polar regions were much closer in temperature. And we have, you know, the five evidence, you know, of five species in these new deposits from Peru, and then also a considerable diversity in the poles at that time. So they were doing quite well in this much earlier period in Earth's history.
FLATOW: But some of them stayed down there to become the penguins of today?
Prof. CLARKE: Well, we don't really know. We don't know where - it suggested that the living diversity of penguins may have also originated in high latitudes and subsequently moved to low latitude regions. We think that, you know, I think it's important to remember that what we have today in the way of penguins it's just essentially a tiny, little twiglet of the penguin family tree. And we think, you know, what we - what certainly the fossil record has taught us is that ecology has evolved and that living penguins very much may be, and appeared to be, cold-adapted species or more cold-adapted than what we think these early species might have been.
FLATOW: Mm-hmm. So we shouldn't be worry about global warming then because these penguins could adapt again to warmer species - to warmer climates?
Prof. CLARKE: Oh, I hope no one gets that message, you know? What we're trying to say is that, you know - what's really striking is the different relationship with global climate change we see early in the penguin lineage. But, of course, you know, species and whole lineages change through times and there are some very important recent studies on global climate and living species of penguins.
But our work doesn't weigh in on that. We're interested in, you know, as paleontologist, in what's going on over millions and millions of years and major changes over that time scale. And what's going on today is happening on a considerably different time scale. So we don't - we are no way implying that the living species that may be cold adapted won't be quite negatively impacted.
FLATOW: Why would a species that you have fossils of existed in a nice, warm climate want to go south, to Antarctica, to live?
Prof. CLARKE: Oh, you mean you sort of...
FLATOW: Why would - yeah, why would they choose if they could be - if they could have stay where they were in a warmer climate? Why would they go to this nightmarish dark spot and freeze their little feet, so to speak, in wintertime?
Prof. CLARKE: It's a very good question. You know, as you remarked in the beginning of the conversation that it appears to be an aberrant thing in penguins that being, you know, breathing on ice. These adaptations to extremely cold conditions may be a very recent and comparatively, you know, aberrant thing for penguins. As to why, we can only speculate.
You know, I don't think our evidence doesn't support that penguins, en mass, you know, that the whole diversity moved to low latitudes and then moved back to high latitudes, but that basically, there was some kind of incentive -perhaps abundant food resources or something - that drove multiple invasions of low latitudes at least twice early in their history and then once more recently.
FLATOW: Mm-hmm. Now I know a lot of people want to know about these new species. Tell us about these five-foot penguins. I mean I've seen in the Antarctica the four-foot, you know, emperor penguins, but I've never seen a five-foot.
Prof. CLARKE: Right. Well, this form - and this is Icadyptes. This is a new species that's 36 million years old. And we did an estimate based on, you know, proportions of its bones compared to the largest known fossil giant penguins, which are from high latitude regions. And it kind of came in about the third largest yet known globally. And so it's around, you know, 4 foot 11. And if you saw it on a Peruvian shoreline or on a dark street corner, you would recognize it as a penguin, you know, for its kind of a rigid, paddle-like wings and the stance. But it has this very striking skull, the first glimpse at the skull of a giant penguin, and it's quite narrow and it's really quite well built, you know? It's a strong, pointed, narrow beak. And, you know, at first glance, it really looks very spear-like.
FLATOW: Yeah, looks like a weapon and the bones.
Prof. CLARKE: Yeah.
Prof. CLARKE: You wouldn't want to meet it necessarily on that dark street corner.
FLATOW: Right. Right. And the other species?
Prof. CLARKE: And the other species is a size of the second largest living penguin. So that's the king penguin. And, again, you would recognize it probably as a penguin, but you might notice some distinctions in the wing structure. And you might also - you would also notice the beak being, again, more pointed, not as elongate as the giant penguin, but still quite distinct in shape from any living penguin today.
FLATOW: Well, I want to thank you very much for taking time to describe these for us. It's fascinating.
Prof. CLARKE: Oh, it's been a pleasure to speak with you.
FLATOW: Thank you. Julia Clarke, assistant professor in the Department of Marine, Earth and Atmospheric Sciences at North Carolina State University in Raleigh.
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