tag:blogger.com,1999:blog-3433304117507034540.post1803062037714373884..comments2024-03-27T10:06:07.100-07:00Comments on The Echinoblog: WHY FIVE? Mysteries in Symmetry! ChrisMhttp://www.blogger.com/profile/11784970666468925633noreply@blogger.comBlogger11125tag:blogger.com,1999:blog-3433304117507034540.post-38419548272163324062020-04-27T17:19:27.778-07:002020-04-27T17:19:27.778-07:00Very interesting read! Thank you!Very interesting read! Thank you!JRinDallashttps://www.blogger.com/profile/11740075917525343137noreply@blogger.comtag:blogger.com,1999:blog-3433304117507034540.post-75875808116777275362020-04-21T10:12:54.385-07:002020-04-21T10:12:54.385-07:00This comment has been removed by a blog administrator.Anonymoushttps://www.blogger.com/profile/14152781608461868686noreply@blogger.comtag:blogger.com,1999:blog-3433304117507034540.post-64860085301853700942016-11-07T13:10:07.567-08:002016-11-07T13:10:07.567-08:00Greetings
All multi-armed sea stars begin at de...Greetings<br /> All multi-armed sea stars begin at development with five arms. After the larvae settle out and they become tiny sea stars. then.. whether its the 6th arm or the other 40 in the Antarctic Labidiaster, subsequent post-primary arms form. the developmental/evolutionary influences are poorly understoood <br /><br />Brittle stars for whatever reason seldom develop more than five rays. Its unclear why that is the case but it remains a difficult question. I have another post showing brittle star diversity with more than 5 rays http://echinoblog.blogspot.fr/2015/09/lets-learn-about-multi-armed-ophiuroids.htmlChrisMhttps://www.blogger.com/profile/11784970666468925633noreply@blogger.comtag:blogger.com,1999:blog-3433304117507034540.post-10700227809898517472016-11-07T03:48:56.994-08:002016-11-07T03:48:56.994-08:00Interested to know your thoughts on how the varian...Interested to know your thoughts on how the variants with six or more might have evolved?<br /><br />i.e. Ophiactis tyleri with it's six arms? - six-armed brittle star<br /><br />Very interesting article.surfparadisohttps://www.blogger.com/profile/13078425529309496065noreply@blogger.comtag:blogger.com,1999:blog-3433304117507034540.post-66906887902051351402016-09-26T20:02:50.376-07:002016-09-26T20:02:50.376-07:00Ugh. Sorry about the grammar mistakes. Ugh. Sorry about the grammar mistakes. Arsenal Fanhttps://www.blogger.com/profile/04703754375057886392noreply@blogger.comtag:blogger.com,1999:blog-3433304117507034540.post-33221383858913533302016-09-26T20:02:00.247-07:002016-09-26T20:02:00.247-07:00I remeber discussing (in short) the Dave Nichols s...I remeber discussing (in short) the Dave Nichols side-corner strength suggestion in zoology and thinking, why not heptagons or nonagons? My own guess would be due because a diminishing return in energy use..more sides may be better but not 'better enough' to be worth the resources or complexity. What do you think?Arsenal Fanhttps://www.blogger.com/profile/04703754375057886392noreply@blogger.comtag:blogger.com,1999:blog-3433304117507034540.post-69347817391768234162015-05-21T04:13:32.814-07:002015-05-21T04:13:32.814-07:00This speculative stuff is really fun.
I like the s...This speculative stuff is really fun.<br />I like the strength argument, though how you could test it is indeed a challenge.<br />Some interesting stuff about bivalve shape and strength here:<br />http://news.rice.edu/2015/05/19/seashell-strength-inspires-stress-tests-2/<br />Cecilynoreply@blogger.comtag:blogger.com,1999:blog-3433304117507034540.post-19095033166850439782015-05-08T10:07:54.858-07:002015-05-08T10:07:54.858-07:00Publish the scientific paper. Not much point in di...Publish the scientific paper. Not much point in discussing something like that here without your data set. ChrisMhttps://www.blogger.com/profile/11784970666468925633noreply@blogger.comtag:blogger.com,1999:blog-3433304117507034540.post-582062228153830642015-05-08T08:08:30.498-07:002015-05-08T08:08:30.498-07:00Hi Chris
Great post. But I would argue that all a...Hi Chris<br /><br />Great post. But I would argue that all asteroids, and even regular urchins, are truly bilateral because of the madreporite position and water vascular system. <br /><br />What are your thoughts on this?Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-3433304117507034540.post-57769536345015393812015-05-06T06:18:01.528-07:002015-05-06T06:18:01.528-07:00Ah. so it is. fixed. Ah. so it is. fixed. ChrisMhttps://www.blogger.com/profile/11784970666468925633noreply@blogger.comtag:blogger.com,1999:blog-3433304117507034540.post-73282137509949203982015-05-06T06:04:41.368-07:002015-05-06T06:04:41.368-07:00Isn't Arkarua pentaradiate ?
http://echinobl...Isn't Arkarua pentaradiate ? <br /><br />http://echinoblog.blogspot.fr/2009/06/raiders-of-lost-arkarua-oldest.htmlAnonymousnoreply@blogger.com