variation

tags: Evolution in Action by AMNH, Congo River, fishes, AMNH, American Museum of Natural History, evolution, variation, biodiversity, Melanie Stiassny, streaming video This video tells the story of speciation in Central Africa's roiling, rapid Lower Congo River. This river is home to an extraordinary assortment of fish -- many truly bizarre. This new video by Science Bulletins, the American Museum of Natural History's current-science video program, features Museum scientists on a quest to understand why so many species have evolved here. Follow Curator of Ichthyology Melanie Stiassny and her…

tags: Inside the Collections: Ichthyology at AMNH, fishes, AMNH, American Museum of Natural History, evolution, variation, biodiversity, Melanie Stiassny, streaming video This video is the first of a new series of behind-the-scenes looks at the collections at the American Museum of Natural History. In this video, Melanie Stiassny, Axelrod Research Curator in the Department of Ichthyology, takes us through the Museum's vast collection of fishes. The Department of Ichthyology, one of the four departments within the Museum's Division of Vertebrate Zoology, houses a collection that comprises more…

To a man with a hammer, said Mark Twain, everything looks like a nail. The better your hammer, I would add, the more nail-like everything looks. In natural selection, Darwin had crafted one of the best hammers of all time. And in chapter 5 of the origin, 'Laws of Variation', you can hear him umming and aahing about various alternative mechanisms of evolutionary change before deciding that, actually, you know what this needs...hold 'er steady...Thwack! How about, for example, the "effect of external conditions" -- "food climate &c.". Well, "Gould believes that birds of the same species are…