Eureka! Heureka! An Astonishing New Ant!

| 71 Comments | 1 TrackBack

by Dr. Alex “Myrmecos” Wild, http://myrmecos.wordpress.com/

This article originally appeared on Myrmecos Blog —PvM

Martialis heureka Rabeling & Verhaagh 2008 drawing by the inimitable Barrett Klein for PNAS

Most scientific discoveries these days emerge through carefully planned and controlled research programs. Every now and again, though, something unexpected just pops up in a distant tropical jungle. Martialis heureka is a fantastic discovery of that old-fashioned kind. This little ant simply walked up to myrmecologist Christian Rabeling in the Brazilian Amazon. It is not only a new species, but an entirely different sort of ant than anything known before.

The remarkable find was announced today in a paper by Rabeling, Manfred Verhaagh (who, a decade ago, collected and subsequently lost the elusive Martialis before he had a chance to properly examine it), and Jeremy Brown in the early edition of PNAS. If the DNA evidence is correct, Martialis is as ancient and as odd as an ant can be and still be called an ant. The lineage emerged right at the dawn of the family and provides a new line of sight back to the elusive ant ancestors.

What do we know about Martialis? Not all that much. We have a single insect that was found walking about in the leaf litter, away from its presumed nesting site. The details of its biology must be inferred from the morphology of the preserved specimen and the DNA sequence of a few genes. Until someone locates live colonies, the situation is a bit like having a well-preserved fossil with a smattering of genetic information.

We can say that Martialis really is an ant and not just another wayward wingless wasp. The insect bears all the telltale traits marking the ant family: a metapleural gland on the thorax, a constricted waist segment, and an elongate first antennal segment. In Rabeling et al’s analysis, DNA sequence from three nuclear genes (18S, 28S, and EF-1alpha) places Martialis outside the rest of the living ants, but only slightly. At left I have drawn up a simplified phylogeny, an amalgamation of Rabeling et al’s finding and the landmark 2006 studies of Brady et al and Moreau et al.

Martialis is blind and pale, traits normally associated with subterranean species. It was collected in rainforest leaf litter, at dusk, near Manaus, Brazil. The elongate mandibles imply a predatory specialization, although on what we do not know. Rabeling et al suggest “annelids, termites, insect larvae, and other soft-bodied arthropods”. The ant has a stinger, as do all the early lineages. The presence of a metaplueral gland—thought to be associated with ant social behavior—indicates that Martialis lives in colonies.

Given the antiquity of the lineage, the temptation to view Martialis as an ur-ant of sorts is strong. E.O. Wilson certainly felt that way when interviewed for a recent NYTimes article:

Dr. Wilson…is trying to contain his excitement: the 14,001st ant species has just been discovered in the soils of a Brazilian forest. He steamrolls any incipient skepticism about the ant’s uniqueness – the new species is a living coelacanth of ants, a primitive throwback to the first ant, a wasp that shed its wings and assigned all its descendants to live in earth, not their ancestral air. The new ant is so alien, Dr. Wilson explains, so unlike any known to earthlings, that it will be named as if it came from another planet.

With due respect to Wilson, such a view is a mistake. Martialis has over 120 million years’ separation since the ur-ant, plenty of time to develop along its own trajectory. The surviving species is not a throwback but a mix of primitive traits retained from the ancestor and unique traits acquired in the elapsed time. The same is true of most other living ants. Those impossibly long jaws, for example, are not present in any of the other early lineages nor in any of the fossils, almost certainly arising in the intervening millenia as Martialis developed a predatory specialization. And even though both Martialis and the next earliest lineage, the Leptanillines, are blind and pale, such traits evolve so readily among other ant groups (see here, here, and here) it is difficult to infer confidently that the ur-ant was also a yellow eyeless wonder.

Rather, Martialis is important because we have a new window backward from which to view the ur-ant. This perspective, when combined with knowledge of the other early lineages (Poneromorphs and Leptanillines), will provide a stronger triangulation on the nature of the first ants. We will be able to infer with greater confidence the sequence of evolutionary events early in ant history. It gives new data where the existing knowledge was fuzzy.

As an example, the most troublesome aspect of current ant phylogenies is uncertainty surrounding the very earliest events in ant evolution. The genetic studies of Moreau (2006) and Brady et al (2006) unexpectedly fingered the subterranean Leptanilline ants as sister to all other species. Further exploration by Brady et al (2006) indicated that the Leptanilline arrangement might be an artifact of the data, leaving myrmecologists feeling a bit like we were back where we started. In Rabeling et al’s work, Martialis falls in exactly the right place to clear up the confusion: the ancient age of Leptanillines is likely real, not an artifact. And Martialis is older still.

Where we go from here will depend on whether someone succeeds in finding living Martialis. The missing link now is not the ant itself but the knowledge about what it does.

Alex Wild is a biologist at the University of Illinois, where he studies the evolutionary history of various groups of insects.


Original Paper: Rabeling, C., Brown, J. M., and Verhaagh, M. 2008. Newly discovered sister lineage sheds light on early ant evolution. Proceedings of the National Academy of Sciences. doi: 10.1073/pnas.0806187105.

Other sources: Brady SG, Fisher BL, Schultz TR, Ward PS (2006) Evaluating alternative hypotheses for the early evolution and diversification of ants. Proc Natl Acad Sci USA 103:18172-18177.
Moreau CS, Bell CD, Vila R, Archibald SB, Pierce NE (2006) Phylogeny of the ants: Diversification in the age of angiosperms. Science 312:101-104.

Specimen images by Rabeling & Verhaagh, used with permission

1 TrackBack

Ants! from Evolving Thoughts on September 23, 2008 1:36 AM

There's a guest post at the Panda's Thumb by myrmidon Alex Wild on the new "primitive" ant just reported. Go read it.... Read More

71 Comments

They are all still ants.…just getting it in before the IDiots…

I love this stuff but I’m cringing on the thought on how this will be warped by creationist minds.

They are all still ants.…

Geeze - I’m sure glad that science doesn’t have to rely on me for these kind of discoveries. I’d have glanced down, thought “Hey - there’s an ant in my house” and stomped variant number 14001 into oblivion.

(And don’t even ask what would have happened if it was a silverfish)

“They are all still ants.…just getting it in before the IDiots…”

Nuts! Beat me to it. :)

I just console myself with…”Yet more gaps in the Darwinist Religion of the so-called Tree of Life”

Alex-

Is there a good, relatively recent, review paper that addresses what the current thinking is wrt to the evolution of eusocial behavior in ants?

I’m kinda curious where more “solitary” species (like some of the “bulldog” ants) are presumed to fit in at this point.

thanks

It is nice to know that there is still a place for old-fashioned naturalizing. Just kick around and see what you can find.

Wayne Francis said:

I love this stuff but I’m cringing on the thought on how this will be warped by creationist minds.

Oh dear yes, a new discovery: “EVOLUTION DISPROVED!”

It is a little bit fascinating to watch the Wile E. Coyote determination in which any odd new fact is pressed into service in the Darwin-bashing cause.

White Rabbit (Greg Goebel) http://www.vectorsite.net/gblog.html

Fascinating stuff. I always get a kick out of “living fossils,” or more precisely organisms that preserve primitive body-plans, whether they be ants, lizards, fishes, or trees.

I do want to make sure I understand, though: this gentleman found _one_ example of this ant, and never saw another one? And the one specimen he did get, he lost? Then where did the genetic data come from?

Minor afterthought: I find myself mildly irritated by comparisons of IDers to Wile E Coyote. Poor Wile E always laid his plans as best he could, but was defeated by a Power larger than himself. IDers’ problem is not in their stars but in themselves: they insist on trying to change the facts to fit their ideology, and facts are not changeable things.

wolfwalker said:

Poor Wile E always laid his plans as best he could, but was defeated by a Power larger than himself. IDers’ problem is not in their stars but in themselves: they insist on trying to change the facts to fit their ideology, and facts are not changeable things.

Yes, the Fates clearly had it in for poor old Wile … but he also had an odd combination of technical ingenuity and poor judgement. You think I’M going to strap on a pair of Acme Rocket Skates?! And the fact that he kept buying stuff from Acme suggests he really had problems with learning from mistakes.

White Rabbit (Greg Goebel) http://www.vectorsite.net/gblog.html

Wayne Francis said:

I love this stuff but I’m cringing on the thought on how this will be warped by creationist minds.

Simple:

There’s only one know specimen. Since it has no known species, it has no parents and this is impossible.

Until science proves that there are more, we have to assume this ant is the result of special creation.

Or maybe it spontaneously mutated from the prevailing ant “kind” into a new creature, proving the veracity of the Noah’s Ark story.

I do want to make sure I understand, though: this gentleman found _one_ example of this ant, and never saw another one? And the one specimen he did get, he lost? Then where did the genetic data come from?

If I am reading it correctly, he found a single ant of the same species ten years ago and lost it. He just rediscovered it and still has this one.

…but they are all still ants!

There. feel better now?

Ichthyic:

Unfortunately for studies of incipient sociality, all known ants are truly eusocial, with a few obvious secondary losses among recent parasitic lineages. Even ants heralded for their supposed “primitive” state- such as the bulldog ants- have a division of labor into morphologically differentiated reproductive and non-reproductive castes. So we don’t have much grist for a proper study of the transition to sociality.

There are a number of fossil stem-group ants (Armaniidae and Sphecomyrminae) that show signs of some sort of transition. Sphecomyrmines have a metapleural gland, suggesting group living, but their antennae are structured so as to give them some trouble with brood care. There’s only so much we can do with fossils, though, as behavior doesn’t preserve so well in amber.

It is *possible* that Martialis could be a subsocial species, as so little about it is known, but I’d not bet on it.

There are much better insect groups out there for studies of the evolution of eusociality. The Halictid bees show all sorts of variation in social behavior, from fully solitary to fully eusocial, with some species even having populations of both. Polistine wasps are also a great group showing a range of behavior.

For those interested, the Creationist spin is here.

What an amazing find (and, wow, another new putative ant subfamily!) I always love these kinds of discoveries.

But – just “walking up to” a myrmecologist? Now we know why it’s so rare. :-)

iml8 said:

wolfwalker said:

Poor Wile E always laid his plans as best he could, but was defeated by a Power larger than himself. IDers’ problem is not in their stars but in themselves: they insist on trying to change the facts to fit their ideology, and facts are not changeable things.

Yes, the Fates clearly had it in for poor old Wile … but he also had an odd combination of technical ingenuity and poor judgement. You think I’M going to strap on a pair of Acme Rocket Skates?! And the fact that he kept buying stuff from Acme suggests he really had problems with learning from mistakes.

White Rabbit (Greg Goebel) http://www.vectorsite.net/gblog.html

I keep thinking that Acme was owned by the Road Runner! 8^)

stevaroni said:

Wayne Francis said:

I love this stuff but I’m cringing on the thought on how this will be warped by creationist minds.

Simple:

There’s only one know specimen. Since it has no known species, it has no parents and this is impossible.

Until science proves that there are more, we have to assume this ant is the result of special creation.

I’m with you on this. The idea that this ant had a parent is a totally unwarranted Darwinian assumption. ID (not creationism) does not take a position on whether the ant was born or not; however, since we know that humans can make things from scratch, the ID inference that the ant was designed is in this case the best explanation.

Alex said:

For those interested, the Creationist spin is here.

Heh! Dramatic radio-announcer voice: “A look inside the paper reveals a few problems with the confident assertions about evolution … “

I can’t read this stuff for long. My eyes glaze over. I can bet that we’ll be getting an essay from the O’Luskin “ID creationism NOT” crowd that reads pretty much the same, but I don’t think anybody would take the bet.

White Rabbit (Greg Goebel) http://www.vectorsite.net/gblog.html

D. P. Robin said:

I keep thinking that Acme was owned by the Road Runner! 8^)

I vaguely recall the Acme catapult (not merely incapable of shooting straight but actually capable of smashing poor Wile E. no matter where he was standing or hiding) had, on close inspection, a Roadrunner logo on the label.

White Rabbit (Greg Goebel) http://www.vectorsite.net/gblog.html

. Even ants heralded for their supposed “primitive” state- such as the bulldog ants- have a division of labor into morphologically differentiated reproductive and non-reproductive castes. So we don’t have much grist for a proper study of the transition to sociality.

I see. For some reason I had thought the bulldog group would be more unique. Thanks for the update.

There are much better insect groups out there for studies of the evolution of eusociality. The Halictid bees show all sorts of variation in social behavior, from fully solitary to fully eusocial, with some species even having populations of both. Polistine wasps are also a great group showing a range of behavior.

There was someone I recall when I was a grad student at Berkeley who had spent much of his time researching the evolution of eusociality in wasps and bees, (it’s been quite a while now and I can’t recall the name), but I found the issue fascinating.

I had assumed there would be more variability within the ants; why do you suppose this is not the case?

Thank you for providing the link Alex. I knew about it already but didn’t want to mention it. I sincerely would like to know how evolutionists respond to the following snippet from the link:

They explained that the supposition that ants evolved from wasps relies on ambiguous data subject to alternative hypotheses. One other problem with their suggestion that ants evolved from wasps is that Martialis would make the ant hypogaeic [underground] foraging evolve three times.

That’s why they are suggesting the basal ant was already a hypogaeic forager. “The exact nature of the ancestral ant remains uncertain,” though, “given that the propensity for repeated evolution of a hypogaeic lifestyle may be higher than for reevolution of an epigaeic lifestyle.”

In short, no clear light seems to have been shed on ant evolution by this discovery.

In short, do y’all agree with these particular assessments in light of the Martialis discovery? Do you disagree? Why?

FL

Where did the cool cladogram of ants come from? (NB that I don’t have subscriptions to science sites like AAAS science.) I don’t know much about the range of adaptations in ants – I suppose I’ll have to at least skim through Wilson’s work on social insects, though it’s like a hundred times more than I need.

Something tells me that Wilson has been unusually cheery the last few days. It’s always nice to see a person in love.

White Rabbit (Greg Goebel) http://www.vectorsite.net/gblog.html

I can’t read this stuff for long. My eyes glaze over.

I got as far as the claim that this critter should be more wasp like since the distant ancestor is presumed to be an early wasp species. Why they didn’t think this guy might have been after the acquisition of ant-like traits, I didn’t read far enough to learn their reasons for claiming that.

Henry

Henry J said:

Why they didn’t think this guy might have been after the acquisition of ant-like traits, I didn’t read far enough to learn their reasons for claiming that.

My own wearisomeness comes from the fact that, since every time I’ve tracked down a Darwin-basher claim it’s always been a quibble at best and a fraud at worst, all I’m going to accomplish in trying to follow their reasoning is get dragged behind a horse through the cactus. There’s only so many times I can hear WOLF! WOLF! before I tune it out.

The pity is that if there WERE people out there who actually had a substantial and interesting critique of evo science, they would have a very hard time making it heard through the dull noise. Of course if they had any sense they wouldn’t publish it on a creationist website, or for that matter even encourage creationists to discuss it.

White Rabbit (Greg Goebel) http://www.vectorsite.net/gblog.html

FL said: In short, do y’all agree with these particular assessments in light of the Martialis discovery? Do you disagree? Why?

With a big sigh of exasperation, is how I respond.

ID supposed problem #1: “They explained that the supposition that ants evolved from wasps relies on ambiguous data subject to alternative hypotheses.”

Sure it does. All data does. So what? Provide us with an alternative instead of just talking about some hypothetical alternative. Then test it. If you find data to support it, biologists will revise their opinion. Until then, wasps are the best candidate. This is a nonproblem.

ID supposed problem #2: “One other problem with their suggestion that ants evolved from wasps is that Martialis would make the ant hypogaeic [underground] foraging evolve three times. “

There is only one problem here - a problem of reading comprehension on the part of IDers. Wild wrote extensively on this point. I don’t see how you could have missed it. But you did, so here you go:

Blindingly obvious answer #2a from the original article: “And even though both Martialis and the next earliest lineage, the Leptanillines, are blind and pale, such traits evolve so readily among other ant groups (see here, here, and here) it is difficult to infer confidently that the ur-ant was also a yellow eyeless wonder.”

Blindingly obvious answer #2b from the original article: “Martialis has over 120 million years’ separation since the ur-ant, plenty of time to develop along its own trajectory. The surviving species is not a throwback but a mix of primitive traits retained from the ancestor and unique traits acquired in the elapsed time.”

You posed us a question and I answered it. So now I’m going to pose you a question: do you think the ID reviewers missed those two big honking explanations in the middle of the piece out of ignorance, or are they trying to decieve their readers by intentionally ignoring them?

I have a Bio 101 question. Dr. Wild implies that the wasp-ant ancestor was a wasp, rather than some critter equally genetically distant from both, and I wanted to know why this is the expectation. Is there some wasp that we know about that hasn’t changed for 120 million years?

eric said:

I have a Bio 101 question. Dr. Wild implies that the wasp-ant ancestor was a wasp, rather than some critter equally genetically distant from both, and I wanted to know why this is the expectation. Is there some wasp that we know about that hasn’t changed for 120 million years?

Technically speaking, ants and bees are two groups of very distinctive wasps (Order Hymenoptera) in the exact same way iguanas and geckos are two groups of very distinctive lizards. Hence Dr Wild is correct in saying that the immediate ancestor of both modern wasps (i.e., yellowjackets, and mud daubers) and ants was a wasp. Now, if he were speaking about the immediate ancestor of all wasps, including Vespa, sawflies, parasitic wasps, as well as bees and ants, then, no, it was not a wasp, per se.

Eric:

Sorry I didn’t clarify this in the post. Ants really *are* wasps. (So are bees, for that matter.) Wasps are an ancient group from which several more specialized lineages- including ants- evolved. This bit isn’t really news- ants were always classified within the wasps in the old Linnean system, and recent, more rigorous phylogenetic analyses of both morphological and molecular data confirm that ants are just a specialized form of wasp. So the story of ant evolution is one of acquisition of new ant characters on top of an ancestral wasp state.

iml8:

The “cool cladogram” is from here. I simplified the tree from the original PNAS paper using the freeware program Mesquite, and appended some images from the myrmecos.net ant photo gallery.

Aren’t there Cretaceous fossil ants,such as Sphecomymodes, which are more intermediate in nature between living ants and other wasps?

Dr. Wild implies that the wasp-ant ancestor was a wasp, rather than some critter equally genetically distant from both, and I wanted to know why this is the expectation.

Starting at the http://tolweb.org/formicidae page and moving upward using the “containing group” links up to apocrita, it looks like ants are rather deeply embedded inside one branch of the wasp clade.

That makes it likely that the ancestor of the apocrita clade had most of the traits prevalent in its descendants, which are mostly wasps.

Henry

Alex said:

The “cool cladogram” is from here. I simplified the tree from the original PNAS paper using the freeware program Mesquite, and appended some images from the myrmecos.net ant photo gallery.

It IS cool – any good sources on the hymenoptera for the nonspecialist online, besides Wikipedia? Dawkins wrote a bit on their “haplodiploid” reproduction … there’s a 1995 NOVA episode on the ants available but only in VHS.

White Rabbit (Greg Goebel) http://www.vectorsite.net/gblog.html

Julie Stahlhut said:

Trouble is, it doesn’t look anything like a wasp, from which ants supposedly evolved…

Even without the caveat that the “eyeball test” can be taxonomically misleading, this is clearly a quote from someone who has never taken a close look at any of the above. Wanna bet that the alleged expert who posted this to Creation “Safari” has never bothered to actually observe live insects?

I’ll wager 20 dollars on that.

Stanton said:

I’ll wager 20 dollars on that.

I think she was looking for someone to bet AGAINST it. Fat chance.

White Rabbit (Greg Goebel) http://www.vectorsite.net/gblog.html

That whole bit about the wasp/ant connection and the Velvet Ant info was very interesting.

I had no idea about those things before.

Thanks for digging it up and explaining it so that even a non-scientist lurker like me can understand it.

(Hanging out at the Panda. Gotta love it.)

It’s sort of like ants are to wasps as early amphibians are to fish.

Henry

Henry J said:

It’s sort of like ants are to wasps as early amphibians are to fish.

Henry

Not exactly: ants are to wasps what mudskippers are to gobies.

Yea I look at it like ants are to wasps like humans are to chimps. We both have been evolving for a few million years and while the ignorant might call our LCA a chimp it really wasn’t.

The LCA of ants and current day wasps might look like a wasp…but then flying Ants look like wasps too.

White Rabbit (Greg Goebel)

ah, your handle triggered a recent news item in my head; hope you aren’t fond of the candy with the same name:

http://www.cbc.ca/consumer/story/20[…]erabbit.html

Ichthyic said:

Hope you aren’t fond of the candy with the same name:

That beats the Chinese toothpaste that used ethylene glycol (antifreeze fluid) as a sweetener. It did a number of people in.

White Rabbit (Greg Goebel) http://www.vectorsite.net/gblog.html

Chinese toothpaste that used ethylene glycol (antifreeze fluid) as a sweetener

then there were the toys with the lead paint…

from last year:

http://www.reuters.com/article/worl[…]andChannel=0

But these were isolated incidents which did not broadly mean Chinese goods and especially its exports were unsafe, insisted Lin Wei, deputy head of the quality inspection bureau’s import and export food safety division.

“We are confident we can guarantee that Chinese products are of good quality and cheap, yet safe and healthy,” he added.

uh huh.

I wonder who’s head is on the chopping block (literally) for this latest?

iml8 said:

wolfwalker said:

Poor Wile E always laid his plans as best he could, but was defeated by a Power larger than himself. IDers’ problem is not in their stars but in themselves: they insist on trying to change the facts to fit their ideology, and facts are not changeable things.

Yes, the Fates clearly had it in for poor old Wile … but he also had an odd combination of technical ingenuity and poor judgement. You think I’M going to strap on a pair of Acme Rocket Skates?! And the fact that he kept buying stuff from Acme suggests he really had problems with learning from mistakes.

White Rabbit (Greg Goebel) http://www.vectorsite.net/gblog.html

One of the great old Ian Frazier stories, “Coyote vs. Acme.”

pianoguy said:

One of the great old Ian Frazier stories, “Coyote vs. Acme.”

I’ve got that in my archives, with the equally witty ACME RESPONDS follow up: “Mr. Coyote’s use of ACME Products was clearly outside of the bounds of the proper operation and application for which these products were designed … “

White Rabbit (Greg Goebel) http://www.vectorsite.net/gblog.html

About this Entry

This page contains a single entry by Guest Contributor published on September 22, 2008 10:54 PM.

Suricata suricatta was the previous entry in this blog.

Ovis canadensis is the next entry in this blog.

Find recent content on the main index or look in the archives to find all content.

Categories

Archives

Author Archives

Powered by Movable Type 4.361

Site Meter