Mantids of the future

[Christian]

You know the termites are now considered cockroaches?

Yes, but they are different enough to deserve an extra mention, I think.

 

[jameslongo]

The present-day Giant Northern Termite or Darwin Termite (Mastotermes darwiniensis) looks to be the link between termites & cockroaches. Still, it is a very primitive species as far as termites go.

You can say this classification debate is comparable to the denunciation of Pluto as a planet.

 

[PhilinYuma]

Yes, but they are different enough to deserve an extra mention, I think.

This is what happens when I take a few sick days. The sky falls in, and suddenly, "termites are now considered cockroaches." My knowledge of cockroaches is small, that of termites, smaller yet, and that of cladistics, infinitesimal, so please show me where are I am wrong, gentlemen, or if I was formerly right, reveal the latest knowledge from the arcane world of systematics so that I may see the light.

O.K. I have a copy, somewhere, of Niels Kristensen's 2000, paper, "Evidence of gene sequencing...." which refuted or "corrected" Kambhampati's 1995 paper in which he said that he could find no genetic relationship between the Blattodea and Isoptera. It is in this paper that we first see (I think) a cladistic diagram that, although still placing mantids, roaches and termites in the same order (Dictyoptera), looks on the common ancestor of the Cryptocercans (Cryptocercus) and termites as being more derived than other roaches. But all this is both old hat and by now, received wisdom. Peter S. Cranston, co editor of Systematic Entomology, and Penny Gullan (are they married, or just good friends? They're both full profs at U.C. Davis) contributed an article to Resh and Carde's Encyclopedia of Insects, (2nd ed.) that came out earlier this year. However, these guys are cladistic systematists (I just made that up. What is the word, cladists, cladocerans? ), not evolutionary systematists like Eriksen, and, as they hardly need point out, by separating Cryptocerus* from the rest of the Blattodea, the order is rendered paraphyletic, i.e., not a true order. I have always seen this, from my narrow, and frankly not desperately excited standpoint as evidence that Cryptocercus are not really Blattodea rather than that Cryptocerus and the Isoptera are anything more than "sister" groups.

I await enlightenment.

* And by another of those great coincidences that were such a turn on for Carl Jung, Orin gives a great account of C. punculatus in the latest copy of Invertebrates Magazine. Buy it.

 

[Christian]

Oh Gee...

Well, this debate is ongoing and no "final" conclusion is achieved yet (by the way, nothing is final in science at any time).

I will try to make it short: Cryptocercus is still a roach, but it is not considered by everyone to be a group of its own, particularly Grandcolas et al. are trying to place this genus among other roach families and regard it just a derived member of the respective family (Polyphagidae).

If to summarize the latest outcomes of Dictyopteran relationships, most agreed to place Mantodea as sister to Blattodea. So far so good. The problem arises when trying to fix up the relationship between termites and roaches. Most genetic studies show termites to be derived roaches and, important in this case, nested between Blattodea. This particular situation requires a renaming of one of the groups, as it is to avoid naming paraphyletic groups. A paraphyletic group is a group which has a common ancestor but does not include all of its descendants. As an example, roaches as an order are paraphyletic with respect to termites, if termites are viewed as an order as well. In order systematics to be in concordance to phylogeny, that is only monophyletic groups to be named (all descendants of a common ancestor with this ancestor being part of the group), one of the two orders must be changed status. Either the roaches should be separated into two or more orders that will stand at level with Isoptera, or Isoptera should be given infraordinal status. And this is what happened, as it is more parsimonious than splitting Blattodea. However, in the original paper by Inward et al. (2007) they went too far and reduced Isoptera to family level, which was not practical and deterred most taxonomists (all families would have to be reduced to subfamilies etc.). So, subsequent work proposed, in concordance to roach taxonomy, to give Isoptera epifamily or infraordinal status. This seems to be the last update if I didn't missed anything. Now the situation is a s follows: Mantodea sister to Blattodea, and Isoptera nested within Blattodea. Let's see what comes next.

 

[Matticus]

Duhh mantises are already that big have you never seen Zorak from Space Ghost! (giant mantis from signature below).Now on a serious matter the whole being to heavy thing doesnt quite add up to me because there insides wouldnt grow sepratly they would grow proportionatly meaning that there bodys at that size would be supporting the same amount of weight as they are now. meaning that there intestines would fall out now at there normal size which they dont. so if your theory is correct the existence of mantids is physically impossible, which we all know isnt, sorry to burst your bubble but i dont think your theory makes any bit of sense please try to prove me wrong! haha on the origional post that would be awesome yet scarry and for it to happen id have to agree with the wasp radioactive powerplant theory.... :blink: ahhhhhh mantids that can fly for long periods and have stingers!!!! Also, i mean hey look at mantispidae theres kinda what it would look like though they are part of the lacewing family.

It's not my theory. It's scientific fact. There's a large difference between a mantid molting and his structure holding in less than 1 ounce of weight in his abdomen, and one molting at 10 ounces and his much larger structure keeping that weight from simply tearing through and falling out while he molts (since during the molting process the exoskeleton is not hard). Go read an entomology textbook, or quite frankly any kids' book about bugs. They may not explain it in this detail, but they'll tell you the same thing.

 

[PhilinYuma]

Oh Gee...Well, this debate is ongoing and no "final" conclusion is achieved yet (by the way, nothing is final in science at any time).

I will try to make it short: Cryptocercus is still a roach, but it is not considered by everyone to be a group of its own, particularly Grandcolas et al. are trying to place this genus among other roach families and regard it just a derived member of the respective family (Polyphagidae).

If to summarize the latest outcomes of Dictyopteran relationships, most agreed to place Mantodea as sister to Blattodea. So far so good. The problem arises when trying to fix up the relationship between termites and roaches. Most genetic studies show termites to be derived roaches and, important in this case, nested between Blattodea. This particular situation requires a renaming of one of the groups, as it is to avoid naming paraphyletic groups. A paraphyletic group is a group which has a common ancestor but does not include all of its descendants. As an example, roaches as an order are paraphyletic with respect to termites, if termites are viewed as an order as well. In order systematics to be in concordance to phylogeny, that is only monophyletic groups to be named (all descendants of a common ancestor with this ancestor being part of the group), one of the two orders must be changed status. Either the roaches should be separated into two or more orders that will stand at level with Isoptera, or Isoptera should be given infraordinal status. And this is what happened, as it is more parsimonious than splitting Blattodea. However, in the original paper by Inward et al. (2007) they went too far and reduced Isoptera to family level, which was not practical and deterred most taxonomists (all families would have to be reduced to subfamilies etc.). So, subsequent work proposed, in concordance to roach taxonomy, to give Isoptera epifamily or infraordinal status. This seems to be the last update if I didn't missed anything. Now the situation is a s follows: Mantodea sister to Blattodea, and Isoptera nested within Blattodea. Let's see what comes next.

If your name is not Christian or Orin (not to mention hypoponeura and a few others), reread the post quoted above, and if there are a few words like "paraphyletic" and "infraordinal" that don't ring a bell, look them up. I had not read Grandcolas, or Inward, et al ("Death of an Order," how dramatic!), or the response by a ragtag band of twelve researchers led by the U. of Sydney ("Save Isoptera," more drama!), etc., but having done so, I can tell you that the topic is worth following and that Christian's brief synopsis of the debate is as good as you are likely to find anywhere.

But how can a discussion of whether or not termites are "really" cockroaches have any importance in the "real world"? One hundred years ago, the theories of Haekel (famously, "ontogeny recapitulates phylogeny") were in their death throes, killed by a reconsideration of the works of Mendel and Darwin whose work had been published half a century before.

I doubt if one person in a thousand could describe the highlights of his theory today, but out of the ashes grew the unifying principle of biology and a declaration of implacable war against far-right American Christianity that has done for Biology what Galileo did for astronomy four hundred years ago. So, 1609, 1909, 2009. I'm not sure that if you ignore history you will be obliged to relive it, but I do believed that it will run you over. Don't get run over.