http://www.hoxfulmonsters.com/2009/04/new-tree-of-animal-suggests-nervous-system-evolved-only-once-in-animal-history/ Who we're........what's our place........ Tue, 02 Feb 2010 16:09:00 -0800 http://wordpress.org/?v=2.8.1 hourly 1 http://www.hoxfulmonsters.com/2009/04/new-tree-of-animal-suggests-nervous-system-evolved-only-once-in-animal-history/comment-page-1/#comment-1552 Sean Sat, 12 Sep 2009 22:31:50 +0000 http://www.hoxfulmonsters.com/?p=1902#comment-1552 Unfortunately I have only been able to access this as the abstract. IF this holds up, it would seem to imply that either Homoscleromorphs independently developed basement membranes or that they existed in the common ancestor and were subsequently lost. As a non-biologist I have a little difficulty assessing how truly homologous eumetazoan and homoscleromorphan basal membranes are, and how likely they are to be convergent by co-opting the same pre-existing pathways (I have read that basement membranes are used in other sponges in making sclerites, but don't know the level of homology). The alternative of secondary loss seems unlikely (I think I may have read that some very simplified parasites may have lost epithelia, but don't know of any other examples). Placing Placozoa between sponges and eumetazoa, also lacking basement membranes, adds to the issue. I would appreciate input from anyone with more knowledge on this issue. Unfortunately I have only been able to access this as the abstract. IF this holds up, it would seem to imply that either Homoscleromorphs independently developed basement membranes or that they existed in the common ancestor and were subsequently lost.
As a non-biologist I have a little difficulty assessing how truly homologous eumetazoan and homoscleromorphan basal membranes are, and how likely they are to be convergent by co-opting the same pre-existing pathways (I have read that basement membranes are used in other sponges in making sclerites, but don’t know the level of homology). The alternative of secondary loss seems unlikely (I think I may have read that some very simplified parasites may have lost epithelia, but don’t know of any other examples). Placing Placozoa between sponges and eumetazoa, also lacking basement membranes, adds to the issue. I would appreciate input from anyone with more knowledge on this issue.

]]> http://www.hoxfulmonsters.com/2009/04/new-tree-of-animal-suggests-nervous-system-evolved-only-once-in-animal-history/comment-page-1/#comment-1060 Wednesday Round Up #63 « Neuroanthropology Wed, 13 May 2009 12:21:44 +0000 http://www.hoxfulmonsters.com/?p=1902#comment-1060 [...] Sambrani, New Tree of Animals Suggests Nervous System Evolved Only Once in Animal History Hoxful Monsters shares research on how we are all just like [...] [...] Sambrani, New Tree of Animals Suggests Nervous System Evolved Only Once in Animal History Hoxful Monsters shares research on how we are all just like [...]

]]> http://www.hoxfulmonsters.com/2009/04/new-tree-of-animal-suggests-nervous-system-evolved-only-once-in-animal-history/comment-page-1/#comment-1030 Carnival of Evolution #11 « OH, FOR THE LOVE OF SCIENCE! Fri, 01 May 2009 23:59:44 +0000 http://www.hoxfulmonsters.com/?p=1902#comment-1030 [...] In the next hall, there was a copy of The Primate Diaries.  The open page said something about how unicolonial ants pose challenge to “selfish gene” theory. Beside it was a Denim and Tweed wall plaque, illustrating how ants trim trees for more living space. The end of the hall had a big sign by Hoxful Monsters, showing a new tree of life, which suggests that the nervous system evolved only once in animal history. [...] [...] In the next hall, there was a copy of The Primate Diaries.  The open page said something about how unicolonial ants pose challenge to “selfish gene” theory. Beside it was a Denim and Tweed wall plaque, illustrating how ants trim trees for more living space. The end of the hall had a big sign by Hoxful Monsters, showing a new tree of life, which suggests that the nervous system evolved only once in animal history. [...]

]]> http://www.hoxfulmonsters.com/2009/04/new-tree-of-animal-suggests-nervous-system-evolved-only-once-in-animal-history/comment-page-1/#comment-1027 New tree of animals suggests nervous system evolved only once in … « Puppy Paradise Wed, 29 Apr 2009 10:23:44 +0000 http://www.hoxfulmonsters.com/?p=1902#comment-1027 [...] View the entire post by clicking here [...] [...] View the entire post by clicking here [...]

]]> http://www.hoxfulmonsters.com/2009/04/new-tree-of-animal-suggests-nervous-system-evolved-only-once-in-animal-history/comment-page-1/#comment-1005 Nagraj Wed, 22 Apr 2009 06:44:44 +0000 http://www.hoxfulmonsters.com/?p=1902#comment-1005 Thanks daniel ......glad that my writings helps you!!!! Thanks daniel ……glad that my writings helps you!!!!

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