tag:blogger.com,1999:blog-6094038346173044955.post8088985483715105966..comments2024-03-27T19:39:11.723-04:00Comments on Parasite of the Day: April 8 - Maritrema novaezealandensis Susan Perkinshttp://www.blogger.com/profile/05944116263349266952noreply@blogger.comBlogger3125tag:blogger.com,1999:blog-6094038346173044955.post-51323071202420787392021-12-15T14:43:02.371-05:002021-12-15T14:43:02.371-05:00I found the interaction between the snail host and...I found the interaction between the snail host and the parasite to be very fascinating. Particularly, it is interesting that the parasite castrates the snail, and that the release of the cercariae from the snail is dependent on temperature. It makes me wonder how this parasite will be affected by climate change. Specifically, if global temperatures increase, will we see an increase in parasite release? I also found it interesting how the killing of the crustacean host by the parasite was described as a type of population control. This phenomenon begs the question: if there are more M. novaezealandensis cercariae released from the snail as global temperatures increase due to climate change, will we see a significant decrease in the crustacean population? Awesome entry! Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-6094038346173044955.post-22804850241908274612011-10-18T07:09:02.474-04:002011-10-18T07:09:02.474-04:00Yes, just about all trematode castrate their snail...Yes, just about all trematode castrate their snail host. There are two ways the hosts have evolve to mitigate the effects of these castrating parasites. <br /><br />Firstly, there is coevolution, so the host and parasite population are in an constant evolutionary race; in every generation, if there happen to be rare individuals that are immune from the parasites, then those individuals that escape parasitism will come to dominate the next generation - vice versa for the parasite to evolve to infect these new host.<br /><br />Secondly, there is host maturation time - it appears that the snails do not become infected until they reach above a certain size threshold, and after that, they almost always become infected (and castrated), thus snails that can reach sexually maturity at an earlier age has an advantage because they will be able to have at least *some* offspring before they eventually become castrated - in fact, that's what Fredensborg (the main author for 2 of the above cited papers) found in his research - snails which are found in areas where parasites are common reach sexual maturity at an earlier age than snails in areas where parasites are rare. This is a pattern which has been found not just for this particular host-parasite system, but also in other host-parasite relationships where the parasite (either through killing or castrating the host) drastically reduces the host's reproductive fitness.Tommy Leunghttps://www.blogger.com/profile/06421993204602775597noreply@blogger.comtag:blogger.com,1999:blog-6094038346173044955.post-76396063484866664392011-10-17T22:14:05.113-04:002011-10-17T22:14:05.113-04:00Does this trematode castrate the snail host? How d...Does this trematode castrate the snail host? How does the species weather that kind of predation level?notElonhttps://www.blogger.com/profile/04857651031212875523noreply@blogger.com