Early embryo formation described in Nature, vol 449, 1049, 25 October 2007. Biologists at University College London, UK and University of Virginia, USA, have studied the process where a single layer of cells forms into three layers during the early stages of embryonic development. The three layers give rise to different organs and structures in the body. The top layer forms the nervous system and skin; the middle layer the musculo-skeletal and blood circulation systems; the bottom layer the inner organs. The researchers found that in birds and mammals the middle layer, called mesoderm, is formed from cell movements in the centre of the embryo under the influence of a growth factor from a cell layer called extra-embryonic endoderm – a cell layer found in birds and mammals but not fish and amphibians. This process is initiated very early in embryonic development, before the formation of a structure named the primitive streak, which defines the centre axis of the body. This means the development of the body is different in birds and mammals compared with fish and amphibians even before any basic body tissues and structures are formed.
Editorial Comment: This study is more proof that Haeckel’s theory that embryos show the process of evolution as they develop is completely false. The theory was actually shown to be wrong in Haeckel’s lifetime, because his drawings of embryos, which are still being presented as evidence for this theory, were proven to be fakes. The falseness of this theory was overwhelmingly proven in 1997 when a British embryologist Michael Richardson published photos of different animal embryos, which showed how different they were. The new study is on embryos much younger than the ones Richardson photographed, and it confirms there is no evidence for evolution in any stage of embryonic development. (Ref. differentiation)
Evidence News 28 Nov 2007