In order to examine the relationship between crowding and growth rate in green hydra (Hydra viridis), we raised animals at various levels of fixed population densities; all new individuals in excess ...

IN NATURE of April 7 a short account is given of the interesting experiments made by Goetsch on the conversion of the green Hydra into a pale Hydra. Some years ago I observed what may be called a ...

Article Published: 19 July 1947 Nutrition and Symbiosis* E. C. OWEN Nature 160, 78–81 (1947) Cite this article ...

Scientists already knew that the tiny aquatic creature Hydra vulgaris had to split its skin open every time it opened its mouth. Now, using a genetically modified organism made with contrasting ...