ADVERTISEMENT
  About the SA Blog Network













Guest Blog

Guest Blog


Commentary invited by editors of Scientific American
Guest Blog HomeAboutContact

The Bizarre, Beetle-Biased World of Social Insect Exploitation

The views expressed are those of the author and are not necessarily those of Scientific American.


Email   PrintPrint



Shimada

Shimada

“I’d been emailing my friend back and forth for several months, planning the trip. He was sure I wouldn’t be disappointed. And then one morning I left. Getting to where he was in Japan took a long time… when he and his students came to pick me up, I hadn’t slept for 30 hours since leaving NYC. The jetlag was tough—my mind was spinning and all I could think about was curling up in a ball. But then he drove out to a remote clearing in the forest. It was pouring with rain; I was umbrellaless and drenched. Then I turned over this rock, the ants cleared and it was just there, walking around—you could see it with your own eyes… and pick it up in your hands! Suddenly they were everywhere… I can’t explain exactly how it felt, but I should tell you, it’s possible that nothing more remarkable may ever happen to me.”

We live on a planet where subjugated minions turn the cogs. Naive to the cold efficiency of their existence, they’re subject to all manner of manipulation and exploitation. But this world could not be further from a depressing hell. It’s filled with profound beauty, bursting with curiosities, and once you know it exists, it pulls you in, enticing you to explore it further. For this isn’t the human world, but a parallel realm where microzoological enigmas parasitize the societies of insects.

Few people know about this world. Entomology luminaries like E. O. Wilson tell us routinely that if we don’t own and run the planet, then social insects do; global ant biomass approximates that of humans, and like us, the ecological pressures ants exert on habitats determine what and how much of which species live where. What’s less well advertised is that ants are victims of their own success. Pervasive habitat-sculptors and resource-hoarders, their nests are home to not just ants, but a diverse menagerie of other organisms that siphon off supplies, prey upon the colony, and live comfortably below its radar with biological stealth technology.

Meet the myrmecophiles: “ant-loving” creatures that rank amongst the bizarrest animals known. Their weird shapes and forms are matched only by their strange behaviours—all part of elaborate mechanisms of deception and mimicry that integrate these creatures seamlessly into colony life. Their biologies are cryptic and largely unexplored; most are scarce or hard to find, and seeing them in nature is a rare privilege. To find them, you could do what one of us did, and take a trip to a rain-soaked mountain in Japan.

Diartiger nest

Diartiger fossulatus, clambering over ant larvae inside a colony of Lasius japonicus

Overturning rocks to expose the ant colonies, you’ll eventually find your quarry: a 2 mm-long, reddish-brown and very odd-looking beetle. This is Diartiger fossulatus, the consummate obligate-myrmecophile. Fully dependent on ants for its very survival, Diartiger walks calmly through the chaos of the disturbed nest. Its peculiar form and unhurried gait attest to a bewildering lifestyle, and seeing it in nature for the first time, you can’t help but wonder how it ended up doing what it does, looking the way it looks.

It seems inexplicable; fewer places could be more hostile for small insects than ant nests. They’re policed with brutal efficiency, using a pheromone code of nestmate recognition. Yet, while most intruders are readily dismembered and consumed, myrmecophiles like Diartiger have deciphered this code and made a living inside ant nests for millions of years. If you can pull it off evolutionarily, adopting this lifestyle brings obvious benefits: access to a climate-controlled home, one that’s well defended and devoid of predators. Then there’s the food—lots of it, be it stored booty, the ants or their brood, or, for the most highly integrated species like Diartiger, liquid food regurgitated directly to your mouth by the workers themselves.

So why don’t more arthropods join the myrmecophile club? Certainly, there are myrmecophilous butterflies, bugs, crickets, millipedes, silverfish, spiders; many different taxonomic groups include a myrmecophilous species or two. But given the species richness of each of these groups, such cases are statistical quirks. For most organisms, the path to becoming a myrmecophile must simply be too challenging, the ant fortress too impenetrable.

An inordinate fondness for myrmecophily

For two groups of organisms however, the same cannot be said. They have jumped the evolutionary hurdle dozens, perhaps hundreds of times, and in so doing, have produced some of the most extraordinary cases of ant exploitation and dependency known. Studying them, and their inherent bias towards myrmecophily, may tell us a lot about this mode of life and how it evolves.

They are two vast beetle subfamilies: Pselaphinae (SEH-LAH-FIN-EE, which includes Diartiger; >9000 species) and Aleocharinae (ALEE-OKA-RIN-EE; >13,000 species)—both members of the most species-rich beetle family of all, rove beetles (Staphylinidae).

There are 58,000 named species of rove beetle, but the true number out there is several fold this total. For the most part, they don’t look like typical beetles: the toughened wing cases (elytra) don’t cover the whole abdomen, leaving most of the abdominal segments exposed. In aleocharines, the exposed segments are flexible and telescoping, and the body form rather narrow; in pselaphines, the abdominal segments are rigid and tightly connected, the body shape more compact.

These groups, with their inherent propensity to jump the ant-shaped hurdle, are particularly illuminating if we want to get out how this lifestyle—with all its contrivances and idiosyncrasies—comes into existence. We can treat each instance of myrmecophily these beetles show as a kind of independent “experimental replicate”. With enough replicates, a picture emerges of what usually happens as these beetles crawl along the evolutionary path, from free-living to an advanced state of myrmecophily.

Evolution of the (predictably) bizarre

Diartiger

Diartiger fossulatus, a member of Clavigerini, showing tufts of yellow hair (trichomes) that ants feed from. Note also the fusions of the abdominal segments and those in the antennae.

What both pselaphines and aleocharines show is that species that exhibit an advanced state of myrmecophily tend to demonstrate analogous elaborate morphological and behavioural modifications. Although moving to life inside ant colonies massively distorts how these beetles appear, the evolutionary endpoints are somewhat predictable. The bizarre, it turns out, can be the norm.

Here’s an example. In pselaphines, the tribe Clavigerini is large (over 350 species, in ~100 genera) and comprised entirely of highly integrated ant colony inhabitants. They rank amongst the most evolutionarily derived myrmecophiles known, with strange fusions of segments within the abdomen and antennae. Glands cover their bodies, and they glisten with oily secretions. They’re fed directly by the ants, via reduced mouthparts that are recessed inside the front of the head; they’re even carried around the nest by the workers, as if they were brood. Diartiger is a member of this tribe.

With a couple of exceptions, all Clavigerini have structures called “trichomes”: bundles of hairs at the at the base of the abdomen and tips of the elytra, that exude chemicals which ants seem to find attractive and tasty. Trichomes likely act as “wicks”, conducting secretions from nearby glands. The chemicals are mysterious, but might be appeasement substances that encourage ants to “adopt” rather than attack the beetles. According to our own unpublished, DNA-based work on pselaphine evolutionary relationships, trichomes have arisen independently an additional four times (at minimum) across the Pselaphinae tree of life. And in two cases, the trichomes have appeared at exactly the same positions on the body as in Clavigerini.

Attapsenius

Attapsenius, a guest of the fungus gardens of South American leaf cutter ants. It has trichomes like members of Clavigerini.

Attapsenius, a distantly related genus found solely within the fungus gardens of leaf cutter ants in South America, serves to demonstrate. The genus is a few paces behind clavigerines on the myrmecophile road, but you can see how it’s converging on the same body plan as Diartiger. It has small trichomes in the same positions; what’s more, its antennal segments are becoming consolidated (normally, pselaphine antennal segments are very distinct, but here the segments are tightly pressed together). You can’t tell, but its mouthparts are also tiny, approaching the state found in Clavigerini.

Songius

Songius hlavaci has trichomes on the sides of the head.

In Songius, a Chinese genus recently described by our friend Zi-Wei Yin, trichomes are again present, but this time sprouting from the sides of the head! Note the shiny, oily surface of this beetle—again similar to Clavigerini.

To maintain permanent acceptance in the nest, these different advanced myrmecophiles seem to have converged on the same solution to the problem. That the same regions of the body have been co-opted suggests that some shared ancestral precursor structure may exist there—a gland, some bristles—which can be readily modified into a device for myrmecophily. So, even when creating the bizarre, evolution seems to follow the path of least resistance.

While these pselaphines show a sophisticated level of ant exploitation, the evolutionary path taken revolves around developing trichomes on their robust and compact bodies. In contrast, aleocharines are a wholly different lineage of rove beetles, and with their flexible bodies, have run a totally different evolutionary track to advanced myrmecophily.

Myrmecoid

Examples of myrmecoid Aleocharinae. From top to bottom: Labidopullus ashei, Beyeria vespa, Pseudomimeciton sp., and Ecitophya bicolor.

One theme aleocharines repeatedly exploit is the evolution of a myrmecoid or “ant-formed” body plan. This is a phenomenon unique to myrmecophiles of that famous poster child of tropical biology: army ants. Famous for forming endless trails that spread through the forest, devouring everything in their path, army ant colonies contain astronomical numbers of workers and an endless, cyclical production of eggs. Although menacing, they’re caloric treasure troves ripe for exploitation. And among the plethora of myrmecophiles that turn up to the party, myrmecoid rove beetles are among the most numerous, and by far the most greatly modified for this lifestyle.

They walk with the ants, and the resemblance is striking; the abdomen is constricted to resemble the narrow waist of an ant, and their segments and limbs are sculpted into forms intricately similar to their hosts. In fact so similar are ant and beetle that an evolutionary tale of mimicry to deceive the vicious host ants is tempting.

Digging into the evidence deeper though, we’re left wondering how looking like an ant should help these beetles at all. For army ants are, for all intents and purposes, blind. They live in a world dictated by odours, pheromonal signals and trails that’s foreign to our visually-biased view of life. It may well be that myrmecoid aleocharines are not trying to deceive the ants with their appearance, but birds and other larger animals.

Many vertebrate predators have learned to scavenge forest floor critters that the roaming army ants scare out of hiding. But these opportunists seldom target the ants themselves, and so the beetles slip by, unnoticed (Kistner and Jacobson 1990). If you’re lucky enough to spend some time with a myrmecoid army ant myrmecophile, you’ll see it grooming the workers, procuring colony-specific odours that they rub over themselves. It’s maintaining a disguise of chemical mimicry, diverting unwanted attention from the ants. Myrmecoid rove beetles are essentially playing two dangerous games of deception: one with the outside freeloaders, the other with their marauding hosts.

Eciton

Myrmecoids walking with their South American army hosts. Top: Ecitophya bicolor with an Eciton burchelli army ant. Bottom: Pseudomimection sp. with the ant Labidus pradator.

Many different evolutionary lines of Aleocharinae have converged on this same ant-mimicking body plan. What is more, although the “classical” army ants found throughout the tropics—Eciton, Dorylus, Aenictus—are closely related, a similar behavioural syndrome has evolved in some distantly related ant genera, such as Letopgenys (Witte and Maschwitz 2000). Remarkably, each such occurrence comes with its own dedicated set of myrmecophilous aleocharines, some of which also have a myrmecoid body form (Hlavac and Janda 2009 provide a beautiful example). Aleocharines have also integrated into termite societies many times, repeatedly evolving a termite-looking “physogastric” body. Yet again, a demonstration of the predictably bizarre.

Preadaptations: breaking the code

Thryoxenus

Thyreoxenus brevitibialis, a “termitophile” with a physogastric body form.

With so many cases of myrmecophily, you have to wonder what it is that biases Pselaphinae and Aleocharinae to this ant-centric way of life. Free-living, non-myrmecophilous members of both subfamilies mostly inhabit tropical and temperate forest floors. They abound in leaf litter and soil where ants roam; some are also found up in the tree canopy—again, a place with lots of ants.

Sharing the same habitat probably makes the shift to myrmecophily much easier, but can’t itself explain the propensity to do so. After all, a great many other groups of organisms frequent the same parts of the forest as ants, and these don’t show the same bias to myrmecophily as aleocharines and pselaphines.

That leaves features of the beetles themselves: morphology, behaviour, perhaps even biochemistry or physiology—any characteristic that helps them avoid attacks, and ultimately, empowers them to break the colony code of intruder detection. What these traits—these preadaptations—are, we cannot be sure of at this time, but let us speculate: we suggest that both aleocharines and pselaphines possess preadaptations to myrmecophily engendered by their respective defence mechanisms.

Most aleocharine tribes with myrmecophilous members possess a defensive gland close to the tip of the abdomen. The gland puffs out a chemical to deter would-be predators, giving the beetle a window to escape. In some myrmecophilous aleocharines, this gland has been modified to produce different kinds of chemicals that appease or attract the ants, allowing the beetle to gain acceptance within the ant society (Stoeffler et al. 2011).

One problem with this explanation is that other groups of rove beetles also have defensive glands, and don’t show the same myrmecophily bias as aleocharines. It might be that, for genetic reasons, the glandular chemistry of aleocharines is easier to reprogram from defence to appeasement than it is in other rove beetles. In some myrmecophilous aleocharines, including many advanced myrmecoid species, the number and types of abdominal glands have multiplied, presumably as part of elaborate colony integration mechanisms. Perhaps compared to other rove beetles, aleocharines innovate this way with relative ease; they may be free from some kind of developmental constraint, and so evolve new glands in novel positions on their bodies quite readily.

Batrisodes

Batrisodes lineaticollis, a North American species which is loosely associated with ants. Members of this genus are sometimes attacked by their host ants.

In pselaphines, the preadaptation is even less clear. Defensive glands exist in some groups (Newton and Thayer 1995), but many myrmecophilous species don’t have them. Instead, the unique body plan of pselaphines might be the preadaptation. Pselaphines aren’t just more compact than other rove beetles; the cuticle is also especially thick, and internally buttressed by a kind of endoskeleton made of strong, chitinous scaffolding (Ohishi 1986; Chandler 2001). These features probably enable pselaphines to withstand physical compression in soil as they force their way through dense or heavy substrates.

Their distinctive physical form may bring an added advantage: it means pselaphines are essentially armoured, and conceivably pretty good at surviving encounters with ants. Indeed, amongst pselaphines, tribes where the body is relatively less “armoured” and compact tend not to evolve myrmecophily. In North American Batrisodes, the beetles have been seen to survive attacks from host ants (Park 1935). Moreover, it’s possible that these brawls serve a purpose, allowing Batrisodes to pick up the colony odour and go undetected inside the nest. One small scuffle for a beetle, one giant leap along the path to myrmecophily.

Myrmecophilology: a subject ripe for exploration

Myrmecophiles are undeniably fascinating, and we want to emphasize that precious little is known about them: the lives they lead, their evolutionary history, indeed the entire biological phenomenon is prime scientific real estate. We touched on behaviours and morphological features that might integrate these insects into colony life, but for the most part, information is scarce. At even the most superficial levels, countless questions are unanswered: what’s the purpose of trichomes? What do they secrete? Are the substances they produce the same in Diartiger, Adranes, Attapsenius and Songius? From what theorised ancestral precursor structure did they evolve? The more you look at these creatures with their curious structures and behaviours, the more they lure you in, begging you to make sense of them.

The fact we can see evolution apparently repeating itself in instances of myrmecophily suggests that there may not be an infinite number of ways to integrate into an ant colony. This kind of approach, comparing diverse species, is, we think, a particularly good way to study myrmecophily. It may help identify preadaptations that make certain groups so prone to sacrifice a free-living existence for a myrmecophilous one. And it may yield generalizable “rules” that govern how myrmecophiles evolve once they’ve broken the code.

Attapsenius inside the fungus gardens of its leaf cutter ant host, and clambering over workers.

Attapsenius inside the fungus gardens of its leaf cutter ant host, and clambering over workers.

Broader scale ecological studies are also needed. Ant societies show different levels of size and complexity: those with derived or “complex” social structures are able to operate larger, “more successful” colonies. But like economic systems in humans, as colony size and complexity increase, so too do the number of loopholes that outsiders can exploit. Primitive ants with their small colonies house few, if any myrmecophiles, whereas elaborate and extensive colonies like those of army and leaf cutter ants can accommodate hundreds (Navarrete-Heredia 2002; Rettenmeyer et al. 2010). The evolutionary pressures these myrmecophiles exert on their hosts are unknown. Ants may be victims of their own success, but to what extent?

Finally, we think that the astonishing numerical diversity of pselaphines and aleocharines, and their predisposition to myrmecophily are no coincidence. When ants became ecologically dominant, they radically changed terrestrial ecosystems and the niches insects could occupy. As Holldobler and Wilson (2005) put it, ants “dominate the central, more stable areas of habitats, whereas solitary insects are best able to flourish in the peripheral, more ephemeral areas”. Not so for aleocharines and pselaphines. They radiated extensively in the very habitats dominated by ants, we think by exploiting the same defensive preadaptations that make these beetles so prone to myrmecophily. And today, they are two of the largest and most abundant animal groups on the surface of the planet.

It’s time we updated the mantra: if we humans don’t own and run the planet, then ants, aleocharines and pselaphines most certainly do.

Harmophorus

Harmophorus

References

Chandler D. S., 2001 Biology, Morphology and Systematics of the Ant-Like Litter Beetles of Australia. Memoirs on Entomology, 15. Associated Publishers.

Hlavac P., Janda M., 2009   A new genus and species of Lomechusini (Coleoptera: Staphylinidae, Aleocharinae) from Papua New Guinea associated with ants of the genus Leptogenys. Zootaxa 2062: 57–64.

Kistner D. H., Jacobson H. R., 1990   Cladistic analysis and taxonomic revision of the ecitophilous tribe Ecitocharini with studies of their behaviour and evolution (Coleoptera, Staphylinidae, Aleocharinae). Sociobiology 17: 333–480.

Navarrete-Heredia J. L., 2002   Beetles associated with Atta and Acromyrmex ants (Hymenoptera: Formicidae: Attini). T Am Entomol Soc 127: 381–429.

Newton A. F., Thayer M. K., 1995 Protopselaphinae new subfamily for Protopselaphus new genus from Malaysia, with a phylogenetic analysis and review of the Omaliine Group of Staphylinidae including Pselaphidae (Coleoptera). In: Pakaluk J, Slipinski SA (Eds.), Biology, Phylogeny, and Classification of Coleoptera: Papers Celebrating the 80th Birthday of Roy A. Crowson, Muzeum i Instytut Zoologii PAN, Warszawa, pp. 221–320.

Ohishi H., 1986   Consideration of internal morphology for the taxonomy of Pselaphidae. Papers on Entomology Presented to Prof. Takehko Nakane in Commemoration of his Retirement: 1–21.

Park O., 1935   Beetles associated with the mound-building ant, Formica ulkei emery. Psyche 42: 216–231.

Rettenmeyer C. W., Rettenmeyer M. E., Joseph J., Berghoff S. M., 2010   The largest animal association centered on one species: the army ant Eciton burchellii and its more than 300 associates. Insectes Sociaux 58: 281–292.

Stoeffler M., Tolasch T., Steidle J. L. M., 2011   Three beetles—three concepts. Different defensive strategies of congeneric myrmecophilous beetles. Behav Ecol Sociobiol 65: 1605–1613.

Wilson E. O., Hölldobler B., 2005   Eusociality: Origin and consequences. Proceedings of the National Academy of Sciences 102: 13367–13371.

Witte V., Maschwitz U., 2000   Raiding and emigration dynamics in the ponerine army ant Leptogenys distinguenda (Hymenoptera, Formicidae). Insectes Sociaux 47: 76–83.

The authors thank Taku Shimada (Tokyo; http://blog.livedoor.jp/antroom/) and Zi-Wei Yin (Shanghai Normal University; http://pselaphinae.blog.com/) for allowing use of their images.

 

Joe Parker and Taro Eldredge About the Author: Joe Parker is a research fellow in the Department of Genetics and Development, Columbia University, NY. From Swansea, UK, he’s a life-long coleopterist who became fascinated with Pselaphinae as a teenager. Their diverse sizes and shapes, in particular the myrmecophilous species, inspired him to study the genetic mechanisms controlling insect morphology. He obtained a PhD from the University of Cambridge on how the dimensions of insect body segments are determined, and continues to work on problems of growth, size and scaling in insects. Simultaneously, he has worked to build a comprehensive DNA-based phylogeny of Pselaphinae, and has a crowdfunding project at petridish.org, to help him finish this work. He is interested in developing model organisms and tools to study myrmecophily at the molecular genetic level. Follow @Pselaphinae on twitter and check out the Pselaphinae facebook page.

Taro Eldredge is a PhD candidate in the Department of Ecology and Evolutionary Biology, at the University of Kansas. Originally from Tokyo, Japan, he’s an evolutionary biologist whose work focuses on aleocharine rove beetles, with a particular fondness for myrmecophilous and termitophilous groups. His PhD work is focused on resolving the evolutionary history of the most primitive members of the Aleocharinae: the tribe Gymnusini. For this project, he will be incorporating various sources of data, including fossils, to understand the role of past climate change on current Gymnusini diversity. He hopes that understanding basal aleocharine relationships will prepare a future in myrmecophilous and termitophilous aleocharine research. Check out his blog and website for all things myrmecoid. Follow on Twitter @Pselaphinae.

The views expressed are those of the author and are not necessarily those of Scientific American.






Comments 11 Comments

Add Comment
  1. 1. Heteromeles 11:44 am 12/10/2012

    Neat article, although I’d quibble that myrmecophiles are running the show. If any parasites are ruling things, then arguably fungi (both mutualistic and parasitic) really are running the ants.

    Anyway, looking at how relatively non-human dogs and cats are, I’d say that humans are much easier for social parasites to spoof than are ants. At least right now. Oh yeah, that’s right, artificial selection isn’t natural selection. Uh-hunh. My bad.

    Link to this
  2. 2. jtdwyer 1:27 pm 12/10/2012

    I’m reminded of the street scenes from “Blade Runner”…

    Link to this
  3. 3. American Muse 5:38 pm 12/10/2012

    Enjoyed the article.

    Link to this
  4. 4. Bill_Crofut 7:16 pm 12/10/2012

    Re: “…[T]wo groups of organisms…have jumped the evolutionary hurdle dozens, perhaps hundreds of times, and in so doing, have produced some of the most extraordinary cases of ant exploitation and dependency known.”

    What is the evidence for the claim?

    Link to this
  5. 5. CS Shelton 7:46 pm 12/10/2012

    @Crofut-

    There are species that are related to each other sharing traits that were not present in a common ancestor, presumably based on at least a few lines of converging evidence, some of which was explicated above and some probably left unsaid for convenience.

    This is pretty standard stuff in biology these days. Zoologists shouldn’t have to re-explain the entire discipline from the ground up every time an uninformed skeptic comes along. I’m just an interested layman and wasn’t left scratchin’ my head by this article.

    Your name seems familiar. Are you just a trollin’ creationist, or genuinely curious?

    Link to this
  6. 6. Bill_Crofut 8:44 am 12/12/2012

    CS Shelton,

    My comments have been posted on a semi-regular basis for approximately 2 years; that would explain the familiarity. In order to answer your question on “trollin,’” you’ll have to define the term. As a Traditional Roman Catholic, militant young-Earth Biblical creationist and geocentrist my interest is in obtaining the evidence for many of the assertions made by evolutionists in the various comments venues.

    Standard “stuff” in biology does not seem to address my initial inquiry. For example, your statement, “There are species that are related to each other sharing traits that were not present in a common ancestor…” seems to be another evolutionist assertion. What is the evidence for the claim? The question is not flippant, but based on a challenge made by a ranking biologist of his time:

    “What such cases like those of anatomical ‘convergence’ and general homology actually demonstrate is that there are large numbers of organisms differing considerably in the details of structure but constructed on the same fundamental plan. However, this is no proof of descent from one original ancestor of this anatomical type. This itself requires proof.”

    [Prof. W. R. Thompson. 1956. Introduction. In: Charles Darwin. Origin of Species. Everyman Library No. 811. London: J. M. Dent and Sons. Reprinted with permission. Evolution Protest Movement. 1967. NEW CHALLENGING ‘INTRODUCTION' TO THE ORIGIN OF SPECIES. Selsey, Sussex: Selsey Press Ltd., pp. 11-12]

    Link to this
  7. 7. Bora Zivkovic 11:12 am 12/12/2012

    @Bill_Crofut – you may notice that there is a word “Scientific” on the top of the page, on the banner. In our articles we discuss fine points of science. Since Creationism is anti-science, can you please stop derailing scientific discussions here and instead go discuss anti-science with fellow anti-scientists somewhere else and leave a science site to scientists and interested people to discuss actual science?

    Link to this
  8. 8. fliesfliesflies 5:48 pm 12/12/2012

    @Bill_Crofut–in response to your first question, the evidence for that claim is that there now exists many many species of beetles that live along side ants in an exploitative fashion. So unless you believe such animals do not exist at all, I don’t understand your question. Perhaps you latched onto that quote because the word “evolutionary” was in there? (And, thus didn’t realize that you weren’t asking the question you thought you were?)

    Based on your later posting, I think you meant to ask something more about there being proof for development of the same traits being evidence of evolution and you seem particularly confused about convergent evolution, perhaps not knowing the definition. Convergent evolution is when you see the same type of structure, say a wing, in different species and conclude based on phylogenetic data (these days based on actually genetic data–which Dr. Parker mentions using to make his statements) that the structure arose independently in each species. For example wings in fruit flies and wing in birds are both used for flying, but their most recent common ancestor (based on genetics these days) did not have wings. Furthermore, the genes and development programs used to create or grow the wing are not the same. Thus, it is an example of convergent evolution. Insects developed wings independently of birds developing their wings.
    Dr. Parker is arguing that in each species of beetle that live with ants, each has independently developed traits which allow them to do so. (And remarkably these traits are similar, which can teach us about “how it’s done” and that seems to be by using scents and secretions to trick the ants.)
    So far this has little to do with proving or disproving evolution as a whole–which I think you were trying to do, but totally missed the boat on. It speaks to whether something evolved independently or not. Based on genetic data one can create a family tree of beetles that shows how closely related species are, who are common and disparate ancestors and who lives with ants. Doing this, Dr. Parker has shown/is showing that the ability to live with ants arose independently multiple times. So if your argument was that he was trying to show there was one species of ant-dwelling beetle that gave rise to all the ant-dwelling beetles, then you read the article wrong and/or did not understand it. If you firmly refuse to believe in evolution, then I guess you believe that God independently created lots of beetle species to live harmoniously with ants? To which I ask–where’s your evidence for that???

    You then present a quote that is perhaps out of context, but based on what you provided seems to state that one cannot assume that because flies have wings and birds have wings, they descended from a common ancestor. No one disagrees with this, and as described, Dr. Parker has actually shown that these beetles have arisen independently. Using a variety of approaches, the most powerful these days being genetics, it is much easier to determine how closely related any two species are (everything is related eventually) and determine when, how, and how many times individual traits have arisen.

    I’d like to also note that I am Roman Catholic and that evolution is accepted by the Catholic church.

    Link to this
  9. 9. Bill_Crofut 12:34 pm 12/13/2012

    Mr. Zivkovic,

    You, and the authors of this web page, have the authority to block my comments. You, as the blog editor, also have the authority to order me to cease posting. If you so order me, your order will be honored.

    If you will allow me to continue, please keep in mind my “anti-science” consists of material quoted from this web page which is the basis for my initial question. Banning me from posting on this web page (as has been done on 4 others) will not answer that initial question.

    Link to this
  10. 10. Bill_Crofut 12:35 pm 12/13/2012

    fliesfliesflies,

    Re: “…unless you believe such animals do not exist at all, I don’t understand your question.”

    Allow me an attempted clarification of my question with another quote from the text of this web page: “With enough replicates, a picture emerges of what usually happens as these beetles crawl along the evolutionary path, from free-living to an advanced state of myrmecophily.”

    What is the evidence that these beetles evolved a state of advanced myrmecophily as opposed to having possessed the trait from the beginning of their existence?

    Re: “I’d like to also note that I am Roman Catholic and that evolution is accepted by the Catholic church.”

    “Some will contend that the theory of evolution, as it is called—-a theory which has not yet been proved beyond contradiction even in the sphere of natural science—-applies to the origin of all things whatsoever. Accepting it without caution, without reservation, they boldly give rein to monistic or pantheistic speculations which represent the whole universe as left at the mercy of a continual process of evolution. Such speculations are eagerly welcomed by the Communists, who find in them a powerful weapon for defending and popularizing their system of dialectical materialism; the whole idea of God is thus to be eradicated from men’s minds.”

    [Pope Pius XII. 1950. HUMANI GENERIS: Encyclical Letter on FALSE TRENDS IN MODERN TEACHING promulgated 12th August. In: FALSE TRENDS IN MODERN TEACHING. 1961. London: Catholic Truth Society, section 5]

    Link to this
  11. 11. TiposDos 5:05 am 09/23/2013

    The post is very informative and I thank the author for choosing this topic and elaborating it so well. You have rightly mentioned that myrmecophiles are really hard to find. Thanks that you were able to spot them and write about them.
    Seo Techniques

    Link to this

Add a Comment
You must sign in or register as a ScientificAmerican.com member to submit a comment.

More from Scientific American

Scientific American Dinosaurs

Get Total Access to our Digital Anthology

1,200 Articles

Order Now - Just $39! >

X

Email this Article

X