tag:blogger.com,1999:blog-5460788270738656369.post1111064277288359546..comments2023-12-24T07:02:43.274+08:00Comments on Catalogue of Organisms: Multifarities Most Horrid (Taxon of the Week: Braconidae)Christopher Taylorhttp://www.blogger.com/profile/11075565866351612441noreply@blogger.comBlogger9125tag:blogger.com,1999:blog-5460788270738656369.post-74834742998668882562009-06-17T06:00:34.480+08:002009-06-17T06:00:34.480+08:00If host-specificity is so common, there must be so...If host-specificity is so common, there must be some advantage to it.<br /><br />I imagine host specificity is really a side effect of adapting to an accustomed host's defenses with tactics that make it less well adapted to other possible hosts. It then has to learn to recognize the host that it has adopted (otherwise-) maladaptive characters on behalf of.Unknownhttps://www.blogger.com/profile/00831355954619691739noreply@blogger.comtag:blogger.com,1999:blog-5460788270738656369.post-32422968864600282902009-06-16T20:02:28.917+08:002009-06-16T20:02:28.917+08:00Another problem with the one nematode-parasite-per...Another problem with the one nematode-parasite-per-species is, of course, that some invertebrates are <i>very</i> small.Andreas Johanssonhttps://www.blogger.com/profile/08802392912541974977noreply@blogger.comtag:blogger.com,1999:blog-5460788270738656369.post-41025524472961794842009-06-16T19:00:57.131+08:002009-06-16T19:00:57.131+08:00Well, there you go. You would think that as someon...Well, there you go. You would think that as someone who still spelt the word "Caenozoic" until reasonably recently, I would remember that...Christopher Taylorhttps://www.blogger.com/profile/11075565866351612441noreply@blogger.comtag:blogger.com,1999:blog-5460788270738656369.post-74636136845738403572009-06-16T18:33:24.807+08:002009-06-16T18:33:24.807+08:00The Greek stem in "Cenozoic" is kaino-, ...The Greek stem in "Cenozoic" is <i>kaino-</i>, not <i>koino-</i>Andreas Johanssonhttps://www.blogger.com/profile/08802392912541974977noreply@blogger.comtag:blogger.com,1999:blog-5460788270738656369.post-53922949272497642732009-06-16T15:48:35.344+08:002009-06-16T15:48:35.344+08:00ncm: I would probably say that both factors (and p...ncm: I would probably say that both factors (and probably more) occur, depending on parasite species, depending on mode of transmission, depending on all sorts of things.<br /><br />Host specificity seems to be a surprisingly difficult thing to predict some times. Among mites of the family Sarcoptidae (scabies mites), for instance, there are many species with very limited host ranges (usually a few closely related bat species - I don't know why bats have such an incredibly high diversity of parasites compared to everything else, but they do), but then you have species like <i>Sarcoptes scabiei</i> which are found on almost every type of mammal, including both placentals and marsupials. Of course, there are also issues with investigative bias - a parasite may not have been recorded from all the hosts it can infect.<br /><br />It looks like <i>Ascaris lumbricoides</i> might be human-specific, depending on whether or not it is truly distinct from the pig-parasitic <i>A. suum</i>.Christopher Taylorhttps://www.blogger.com/profile/11075565866351612441noreply@blogger.comtag:blogger.com,1999:blog-5460788270738656369.post-63108842145883564452009-06-16T14:29:41.406+08:002009-06-16T14:29:41.406+08:00I'm wondering if parasites jump from one host ...I'm wondering if parasites jump from one host species to another opportunistically -- i.e., my regular host doesn't seem to be here, let's try this random creature -- or just through failing to recognize that they are in fact jumping species, because they aren't terribly good at such recognition. (You might be able to test this by supplying mixed populations and seeing whether a parasite only attacks other species when there are none of its accustomed host.) Probably plenty of both, I suppose, depending on where you look.<br /><br />Are there really nematodes that only attack <i>H. sap</i>?Unknownhttps://www.blogger.com/profile/00831355954619691739noreply@blogger.comtag:blogger.com,1999:blog-5460788270738656369.post-54369463977043649982009-06-16T07:53:06.311+08:002009-06-16T07:53:06.311+08:00Andreas: I don't know of any nematodes parasit...Andreas: I don't know of any nematodes <i>parasitising</i> other nematodes (and I suspect there might be physical limits preventing that), but I'm willing to be that there's nematodes that <i>predate</i> other nematodes.<br /><br />On the other hand, I'm getting the impression that in many cases the "host specificity" of parasites has been vastly over-estimated, so the "at least one parasite for every species" estimate might not work out so smoothly.<br /><br />Mike: I don't actually know what the specific derivation of "koinobiont" is. I'd guessed that it referred to the close association of host and parasitoid ("close" as in "Cenozoic"), but your suggestion makes even more sense.Christopher Taylorhttps://www.blogger.com/profile/11075565866351612441noreply@blogger.comtag:blogger.com,1999:blog-5460788270738656369.post-74670729162078066632009-06-16T01:00:14.654+08:002009-06-16T01:00:14.654+08:00"koinobiont"
Nifty word I've never ..."koinobiont"<br /><br />Nifty word I've never seen before. Same root as "Koine Greek" (common Greek), I take it? (I.e., the lifeforms mature "in common", so to speak?)Mike Keeseyhttps://www.blogger.com/profile/00147156174467903264noreply@blogger.comtag:blogger.com,1999:blog-5460788270738656369.post-50720644282067540452009-06-15T23:08:23.801+08:002009-06-15T23:08:23.801+08:00Personally, I'm still taking the long odds and...<i>Personally, I'm still taking the long odds and backing the nematodes.</i><br /><br />Someone, I forget who, suggested that <b>every</b> non-nematode animal species has at leaste one nematode species dedicated to parasitizing it and it only. Which leads to the question: are there any nematodes parasitizing other nematodes?Andreas Johanssonhttps://www.blogger.com/profile/08802392912541974977noreply@blogger.com