THE most important criticism in the review on May 13 of “The Origin of Vertebrates,” by Dr. W. H. Gaskell, is based on a dogmatic view as to the fundamental distinctness of the germ layers and their ...

Researchers have discovered that microRNAs play an important role in embryonic development. The study pinpoints two microRNA families that direct the allocation of cells into the three germ layers -- ...

Paediatric head and neck teratomas are rare and present diagnostic challenges. We report a case of a toddler with a recurrent growth in her upper jaw, initially removed at birth and diagnosed as ...

How did the gut, the skin and musculature evolve? This question concerns scientists for more than a century. Through the investigation of the embryonic development of sea anemones, a very old animal ...

Proceedings of the Royal Society of London. Series B, Biological Sciences, Vol. 134, No. 876 (Jul. 2, 1947), pp. 377-398 (30 pages) A critical study and demonstration of the distribution of yolk ...

Researchers offer a phylogenetic and ontogenetic overview of the primitive streak and its role in mediating amniote (vertebrate animals that develop on land) gastrulation, and discuss the implications ...

How does the “body” take shape? The body of animals is highly complex, containing distinct regions that carry out specific functions. As the body forms during embryogenesis, three germ layers are ...

Descriptions of the embryo go back at least to the time of Aristotle, but it has only been since the late 19 th century and early 20 th century that advances in experimental approaches allowed ...

Teratomas are embryonal tumors that arise in the germ cells and contain different types of tissues, including bone, teeth, hair, and muscle. 1 Scientists have classified teratomas as a rare type of ...

PERHAPS the reviewer should have made it plainer that the difficulty he stated at the top of p. 303 is not admitted by those morphologists who have ceased to believe that the germ layers afford any ...

In their publication in Science, Professor Guojun Sheng (Kumamoto University, Japan), Professor Alfonso Martinez Arias (Universidad Pompeu Fabra, Spain) and Professor Ann Sutherland (University of ...