A prehistoric bronze artifact made from a cast has been found in Alaska, apparently a buckle.

There was no Bronze Age in Alaska, though it existed several thousand years earlier in Europe and Asia.  Perhaps some of the earliest Inupiat Eskimos in northwest Alaska, thought to have migrated into Alaska from adjacent Siberia some 1,500 years ago, might have brought the object with them from the other side of the Bering Strait. The Inupiat Eskimos are believed to have occupied Cape Espenberg from about A.D. 1000 until the mid-1800s, said Hoffecker. They are part of the indigenous Eskimo culture that lives in Earth's circumpolar regions like Alaska, Siberia and Canada.

Biodiversity is declining, and is likely to continue along the same path unless something is done about it. And to effectively do something about it, it appears that large investments are required. These substantial investments will probably result in a critical assessment of the science underlying the current and near-future efforts. After all, people and governments like to know where their money goes. This led to a survey among conservation scientists, of which the results have recently been published in the journal Conservation Biology. In the words of the author:

Red blood cells regenerate every four months but the lining of the intestine regenerates itself every few days. The cells that help humans absorb food are constantly being produced and the various cell types that do this come from stem cells that reside deep in the inner recesses of the accordion-like folds of the intestines, called villi and crypts. 

Like ancient burial crypts, these adult stem cells are something of a mystery. Two types of intestinal stem cells have been proposed to exist but the relationship between them has been unclear. One type of stem cell divides slowly and resides at the sides of intestinal crypts. The other divides much more quickly and resides at the bottom of the crypts.