Helen FieldsScience Writer

Send these Neanderthals to the dentist! For a study published last month in PNAS, an anthropology grad student used dental tools to scrape hardened plaque off the teeth of Neanderthals. She wasn’t trying to help them avoid tooth decay. They’d been dead for tens of thousands of years. She was looking inside the deposits for starch grains and other bits of trapped plant matter. This is helping to settle a debate about what Neanderthals ate, which could help explain why they went extinct.

You may remember – Neanderthals are another species of human. They’re in the genus Homo, just like us. We even overlapped a bit, in Europe. Our genomes tell us there was some interbreeding. But modern humans took over and the Neanderthals went extinct. Nobody knows why, and one hypothesis is that it was because they only ate meat, and they just couldn’t get enough calories to compete with modern humans.

The new study shows: Nope, they were definitely eating plants. The researchers were even able to figure out that a lot of what they saw in the plaque came from grasses, relatives of the oats and barley and whatnot that humans got into later. There were even grains of starch that had been cooked. So the all-meat hypothesis is wrong, and also: they were cooking! Whoa!

I wrote about this for Science; you can read it here if you’re a subscriber.

photo: Amanda Henry

Meerkats are adorable little mongooses that live in the Kalahari Desert in tight social groups. Each group is dominated by a female who does most of the reproducing. Others help raise her pups, even lactating so they can nurse them.

This sort of thing happens in many corners of the animal kingdom. Look at ants, for example. In a lot of ant species, one female, the queen, does all the reproduction while her daughters do all the child-rearing and other work.

It’s pretty clear what’s in it for the dominant female. She gets to have tons of offspring and help raising them. But the division of reproductive labor isn’t absolute; subordinates sometimes reproduce, too. This week I wrote about a study that tried to work out why that happens in meerkats.

Biologists have come up with a whole lot of well-thought-out theory on how social systems work, but to test this stuff in the real world, you have to spend a long time watching animals up close. This meerkat study has been going on since 1993, with people in the field working on it full-time. Here’s my story. Uh – there’s a lot of theory. Enjoy.

Cute meerkat detail: They’re easy to train with crumbs of hard-boiled egg, and three times a day they step on the scales to be weighed.

photo credit: Russell Venn

A friend asked if I referenced the CHON movie in my story about the origins of life. I did not. Which is tragic, really – the CHON movie is an absolute classic of science cinema, and for more than a decade now it’s been a required stop on the Helen Fields Tour of the Smithsonian. (It ranks below the Hope Diamond, which everyone wants to see despite the fact that it is just a sparkly rock, and above the artifacts from Troy, which are less exciting than you’d expect.) It plays in a little theater area off the dinosaur hall, although the last couple of times I stopped by, it was not running, which makes me nervous.

Enter…the internet. Now you, too, can watch and learn why we call it the CHON movie, even though its title is “Enter Life.” This version of the video doesn’t have the narration, but I think you’ll be able to follow it anyway. And no narration means you can pay more attention to the catchy tunes.

A new study finds that bird lice have evolved cryptic coloration. (What you or I might call camouflage.) Read my tiny story about it here.

Sulfur-crested cockatoos are awesome. This is my favorite fact about a trip I took to Australia in 1996: instead of pigeons, the parks have flocks of sulfur-crested cockatoos. At least, the parks I remember. Ok, I actually have a lot of favorite facts about Australia, like the fact that the kangaroos in Carnarvon National Park were total pests and kept trying to steal food from the picnic tables. Also, we were on Heron Island during the time when the female sea turtles were coming on shore to lay their eggs and the babies from earlier nests were hatching out and swimming out to sea (where probably most of them became shark snacks).

Man. Australia was cool.

When I was in Kansas last weekend, we skipped over the border to Missouri to see a nice exhibit of rare books from the History of Science Collection at the Linda Hall Library. This library is kind of a surprise – when we were there, I assumed it was part of a university, but it’s actually an independent public library of science, engineering and technology. Herbert and Linda Hall had a lot of money, and this is what they left it to: a public library.

The exhibit shows the tradition of natural history that Darwin came from. His theory of natural selection was based on years of careful study of different kinds of animals – he knew more than anyone about barnacles, for example, and of course there were his famous Galápagos finches. Natural history is a darn good way to learn about nature.

Most of the displays were illustrations from books back to the 15th century. Back then, people were sort of conflicted between relying on classical texts – it was the Renaissance, they were really into that stuff – and observing plants and animals in nature.Some of the pictures had clearly been done by people who had never seen the animal in question, and the texts often came from the ancient Greeks. But eventually they started figuring out that they should actually be observing the animals they were writing about. (Whoa! Crazy talk!)

This adorable hedgehog was in a 1551 book, Historia Animalium:

Isn’t it spunky? (The label says “bristling with charm.”)

Here are some copepods from a book published in 1820 in Geneva. Copepods are teeny crustaceans – relatives of crabs and shrimp.

I was excited to see these guys because I saw a lot of copepods in the Bering Sea last spring. I wrote stories about copepods on at least four days, but see this day for some really nice copepod portraits. (My fingers got really, really cold while Chris was taking the pictures of the glow-in-the-dark copepods, so be sure to go appreciate the beauty.)

This Portuguese Man O’ War was collected in the deep sea in the 1820s.

That is one pretty jellyfish.

From a book published around 1860, a gorilla:

The gorilla was only scientifically described in 1847. Doesn’t that seem late? I mean, gorillas are really big! And that scientific description was just based on bones; apparently no Westerner saw a live gorilla until the 1850s. Chimps and orangutans were already pretty well known by then. (You can read a little gorilla history in this 1988 newsletter – it’s the first story.)

The library had a copy of On the Origin of Species on display, but I failed to take a picture of it because, um, it was just words, see. There were no pretty pictures of animals. Oops.

So, instead, I will leave you with a picture of my best Scrabble play ever, that night at my aunt and uncle’s house:

I played “EQUINELY” for 239 points. This was made possible by two factors: (1) my uncle doesn’t play defensively, so he put that Q right up there by that triple word score, and (2) in our rules, you can look up words before you play them. I wouldn’t have taken a chance on “equinely” if this had been a challenge game, but I thought it might be a word, and I checked the scrabble dictionary, and it was. Woo. Hoo.

For all my Museum Tourist posts, click here.

photos: me, and they aren’t that good, are they? books behind glass. kind of a rough subject.

Yesterday I wrote about turtles. Turtles are awesome. Their shell is made of bone. Bone! Ok, the part you actually touch, the outside, is made of – guess what – tortoiseshell. It’s something like horn. But under that, the hard stuff is made of ribs and vertebrae, fused together. You can see it in the green turtle skeleton at left – sea turtles like this one have big holes in their shell because they don’t really need as much shell as land turtles. (In a land turtle skeleton, that would all be solid.)

Anyway, the truly wacky thing about this arrangement is that the shoulder blades are in front of the ribs. In front! That is weird! As evolutionary morphologist Ann Burke told me: “If you take a deep breath and shrug your shoulders, you realize how bizarre it would be if your shoulder blades were stuck inside your ribcage.” Tetrapods like you and me and cats and birds, we pretty much all have more or less the body plan. But not the turtles. They’re all, “Hey, watch, guys, I can put my ribs behind my shoulder blades.”

I was using my highly sophisticated technique for finding sources who are named in the references of an article – googling burke turtle evolution - and it seemed like, whoever I named, I would get a link to this article from creation.com. So, that’s interesting.  Several scientists I talked to mentioned that turtles do more or less spring fully formed into the fossil record. To creationists, that means someone must’ve placed them there.

This whole thing really made me want to go down to the National Museum of Natural History and look at the turtle skeletons. It’s very old-school: a big long hallway with unsexily displayed skeletons, like this. I love it.

art credit: FCIT

P.S. Hey, I just noticed: this is my 100th post on this blog! Howdya like that?

Yesterday I wrote for ScienceNOW about how piranhas got their pointy teeth. The main thing I learned about piranhas is, really, they aren’t that bad. I talked to two people who have spent a lot of time catching piranhas in the wild and neither has been bitten, other than a little friendly snapping when the piranha was already out of the water. One had a friend who was bitten, though, and it was kind of nasty – the fish took out a chunk of flesh and the guy had to go to the hospital.

I was writing about this guy, Megapiranha – he’s a 3-foot-long extinct piranha relative with interesting teeth. (If you are a person who is interested in piranha evolution.)

Also totally cool: the pacus, which are related to piranhas and look a lot like them, but don’t eat meat. To quote John Lundberg, one of the ichthyologists I talked to: “They really are frugivores. It’s pretty amazing. The pacus that are in the Amazon and Orinoco, they’ll go into flooded forests during the high water season and they’ll wait underneath fruit trees that are coming into maturity. They’ll just hang out. The fruits drop into the water and they float away. Of course the fishermen see that and they fish with fruit.”

Isn’t that funny? Forget nightcrawlers, somebody get this fish a nice juicy piece o’ fruit. He says he watched fishermen in Suriname take a really long pole and put a piece of fruit on the end – something that looks kind of like a kiwi – and slap the fruit on the water. The pacus totally go for it.

art copyright Ray Troll, 2005