Talk:Heterochrony/Archive 1

Archive 1

Just a question

It is called heterochrony when some parts of the anatomy grows faster and/or slower than other parts of the body. But what about traits that don't have anything to do with the anatomy, like if a boy can grow a beard when he is ten years old, but still is like a normal boy in all other ways? I'm not thinking on paedomorphosis, which is defined by sexual maturity in a body that is still on a very early stage in its developement what the rest of the body is conserned. I'm talking about traits that don't have anything to do with the gonads or the anatomy, and which we usually only sees in adults. Traits that can occure with or without sexual maturity in the young individ, but still on such an early stage where you would not expect to find them. Is this still called heterochrony, or is it named something else?

This article seems to be relevant: PMID 14756337. I just found it and have not yet read it. --JWSchmidt 05:02, 17 October 2005 (UTC)

Thank you

I'm currently fixing articles on paedomorphosis, neoteny, progenesis and paedogenesis (all forms of heterochrony), and this is the the first article in the field that isn't erroneous. --Waterspyder 23:14, 19 November 2005 (UTC)

I am not sure about this sentence "If the offset is delayed and the rate is unaffected, the tail will be also larger". Should that not be "smaller"?. Pukkie 05:29, 5 September 2007 (UTC)

If the offset refers to the time when growth of the tail ends, then larger would be correct (this is the way I understood it). 99.20.66.27 (talk) 20:14, 31 October 2011 (UTC)

Two more questions

Thanks for the reply. There are some more things about this kind of evolution which is still not clear.

If I have understood it correctly, when an animal with a larval form becomes sexual mature without going through the metamorphosis to the adult form (the rest of the development stops), it is called progenesis (paedeomorphosis).

But what is the opposite called? Sometimes animals with a larval stages developes directly from an embryo into small juveniles, eliminating the larval stage completely. Many salps in the group Tunicata don't have a larval stage any more. Some frogs who lay eggs on land turn directly into small frogs instead of turning into tadpoles first. Molluscs originally had one (or more) larval stage too, but cephalopods do no longer have them, and turn directly into juveniles. The same thing can be said about annelids like the leeches.

In progenesis the metamorphosis is gone because the larva never turns into a juvenlie or an adult. The metamorphosis is also gone in species where there no longer is a larval stage because they are transformed directly into juveniles, even if their ancestors had to go through a metamorphosis first. But I have no idea what this phenomena is called, and neither can I find any information about it. So, does anyone know if there is a name for it?

Also, is there a name for the phenomena when animals with direct development evolve larval stages secondary, as the case is with most insects?

Thank you wikipedia!

I did not know what heterochrony is until I reached this page (and several research articles). Although wikipedia is not considered a valid source, it is a very handy site to expediently get information. Luna oul (talk) 04:50, 9 October 2013 (UTC)

Too much focus on tails

Why not write about the whole organism, and use the tale as an example instead of writing about the tale only?2A02:FE0:C900:1:ADC4:D2C2:F604:A44D (talk) 06:06, 28 March 2014 (UTC)