Mesoderm is one of the three germ layers, groups of cells that interact early during the embryonic life of animals and from which organs and tissues form.
Baer, Karl Ernst von, 1792-1876
"The Spandrels of San Marco and the Panglossian Paradigm: A Critique of the Adaptationist Programme," hereafter called "The Spandrels," is an article written by Stephen J. Gould and Richard C. Lewontin published in the Proceedings of the Royal Society of London in 1979. The paper emphasizes issues with
Johann Friedrich Meckel and Antoine Etienne Reynaud Augustin Serres developed in the early 1800s the basic principles of what later became called the Meckel-Serres Law. Meckel and Serres both argued that fetal deformities result when development prematurely stops, and they
A germ layer is a group of cells in an embryo that interact with each other as the embryo develops and contribute to the formation of all organs and tissues. All animals, except perhaps sponges, form two or three germ layers.
Ectoderm is one of three germ layers—groups of cells that coalesce early during the embryonic life of all animals except maybe sponges, and from which organs and tissues form. As an embryo develops, a single fertilized cell progresses through multiple rounds of cell division.
"Mutual Affinities of Organic Beings: Morphology: Embryology: Rudimentary Organs" is the thirteenth chapter of Charles Darwin's book The Origin of Species, first published in England in 1859. The book details part of Darwin's argument for the common