tag:blogger.com,1999:blog-5334048668354898660.post4812589014571601223..comments2024-01-08T19:01:37.331+00:00Comments on Donegal Wildlife: UpdatesStuarthttp://www.blogger.com/profile/15225743105419715015noreply@blogger.comBlogger6125tag:blogger.com,1999:blog-5334048668354898660.post-6838725576024828902008-09-24T10:45:00.000+01:002008-09-24T10:45:00.000+01:00"There is a lot of anti-rejection in this process,..."There is a lot of anti-rejection in this process, and I suspect that the host will reject the secondary parasite quite effectively."<BR/>Ah, yes, I hadn't taken that into account - chemical presumably. Fascinating.Gillhttps://www.blogger.com/profile/15736035484977149890noreply@blogger.comtag:blogger.com,1999:blog-5334048668354898660.post-25902064860914780342008-09-24T02:18:00.000+01:002008-09-24T02:18:00.000+01:00>I wonder why the secondary parasite doesn'...>I wonder why the secondary parasite doesn't wait a bit till the primary one has hatched - a larva would be a hell of a lot easier to hit than an egg!<BR/><BR/>It might well do.<BR/><BR/>>Are you suggesting that all bar one of the eggs laid by the straddling ich fail to hatch, or at least fail to hatch so the grub can find the primary parasite and so dies?<BR/><BR/>Most certainly.<BR/><BR/>>under those circumstances surely it'd simply eat the sawfly larva wouldn't it?<BR/><BR/>I don't think so, otherwise it would just be a primary parasite. There is a lot of anti-rejection in this process, and I suspect that the host will reject the secondaty parasite quite effectively.<BR/><BR/>In terms of size, the primary parasite is slightly larger than the secondary parasite, so there wouldn't be enough food left for more than 1 anyway.Stuarthttps://www.blogger.com/profile/15225743105419715015noreply@blogger.comtag:blogger.com,1999:blog-5334048668354898660.post-36196787959430908592008-09-23T23:30:00.000+01:002008-09-23T23:30:00.000+01:00Hmm - I wonder why the secondary parasite doesn't ...Hmm - I wonder why the secondary parasite doesn't wait a bit till the primary one has hatched - a larva would be a hell of a lot easier to hit than an egg! Are you suggesting that all bar one of the eggs laid by the straddling ich fail to hatch, or at least fail to hatch so the grub can find the primary parasite and so dies? - under those circumstances surely it'd simply eat the sawfly larva wouldn't it?Gillhttps://www.blogger.com/profile/15736035484977149890noreply@blogger.comtag:blogger.com,1999:blog-5334048668354898660.post-37084788508304319572008-09-20T00:40:00.000+01:002008-09-20T00:40:00.000+01:00On reflection, I think I have the crux of the matt...On reflection, I think I have the crux of the matter. We know that the secondary parasite lays more than one egg...I showed the sequence last year. Now...the primary parasite has a very large target to hit (the whole larva), so it will lay an egg in the host in a vast majority of attempts. The secondary parasite has to hit the egg of the primary parasite, which will be extremely difficult. So it lays a few in the hope that one will hit. Many attempts will fail. There we have it. The secondary parasite is less advantaged by the paralysis, so the whole sequence works.<BR/><BR/>QED.Stuarthttps://www.blogger.com/profile/15225743105419715015noreply@blogger.comtag:blogger.com,1999:blog-5334048668354898660.post-61658877066410471462008-09-19T23:51:00.000+01:002008-09-19T23:51:00.000+01:00The whole concept of causing a circumstance which ...The whole concept of causing a circumstance which benefits a species that is your predator is counter-intuitive. However, if that circumstance so benefits your predator to an extent that it would wipe you out, then the predator would also perforce die out. So we are left with the conclusion that the paralysing effect of the primary parasite benefits the primary parasite more than it benefits the secondary parasite, however that benefit may manifest itself. Truly wonderful.Stuarthttps://www.blogger.com/profile/15225743105419715015noreply@blogger.comtag:blogger.com,1999:blog-5334048668354898660.post-81784869378572111292008-09-19T16:12:00.000+01:002008-09-19T16:12:00.000+01:00"I suspect that the Campodorus egg subdues the Nem..."I suspect that the Campodorus egg subdues the Nematus larva to some extent (but why?..."<BR/><BR/>um, by accident? That it just so happens that the egg or early-stage larva interferes with the sawfly's nervous system. And both parasite and hyperparasite have 'learnt' to interpret / use that behaviour. I suppose a number of complicated behavioural traits may originally have evolved in this way.<BR/><BR/>The more one learns about species inter-relationships in nature the more one marvels.<BR/><BR/>Nice shot of the spores by the way.Gillhttps://www.blogger.com/profile/15736035484977149890noreply@blogger.com