Silicon Investor (SI) -- The First Internet Community

STOCKTALK

We've detected that you're using an ad content blocking browser plug-in or feature. Ads provide a critical source of revenue to the continued operation of Silicon Investor. We ask that you disable ad blocking while on Silicon Investor in the best interests of our community. If you are not using an ad blocker but are still receiving this message, make sure your browser's tracking protection is set to the 'standard' level.

Politics : Formerly About Advanced Micro Devices -- Ignore unavailable to you. Want to Upgrade?

To: combjelly who wrote (232267)	5/10/2005 10:30:45 PM
From: neolib	Read Replies (1) \| Respond to of 1572958

The old "Ontogeny Recapitulates Phylogeny". Umm, no. That has been successfully challenged a very long time ago. A fact that seems to have managed to avoid being included in highschool biology... Be careful. The idea that an embryo goes through the historical evolutionary progression is no longer held, but what is now held is that comparative embryology makes a very powerful argument for common descent. The basic body plans of a very wide range of related species shows similarities in fetus development that shed light on how our respective bodies are fashioned from the same basic genes. So the fourth embryo stage (pharyngula) when the Hox genes are patterning the major organs and body structure has a very remarkable pattern, the pharyngula arches in vertebrate embryos. This is the so called "gills" in human embryos, and indeed, the pharyngula arches form the gill structure in vertebrate fish, as well as facial, jaw, and ear structures in other vertebrates.

To: combjelly who wrote (232267)	5/10/2005 10:59:14 PM
From: tejek	Respond to of 1572958

"Don't you also think that progress of the fetus during natal development is a speeded up version of evolution where gills are developed then dropped or a tail protrudes and then recedes?" The old "Ontogeny Recapitulates Phylogeny". Umm, no. That has been successfully challenged a very long time ago. A fact that seems to have managed to avoid being included in highschool biology... If so, what is the reasoning behind the formation of gills and the tail during natal development? ted