Fossil Poop Controversy
I.M. Chait auctioneer will soon be taking bids on what it describes as the "longest example of coprolite [i.e. fossil poop] ever to be offered at auction." At 40 inches, it's definitely quite long.
A number of sites described this as dinosaur poop, which it can't be, since it's 40 million years too young to have come from the rear end of a dinosaur.
But gawker's antiviral notes that it may not be a coprolite either. The object comes from Washington's Wilkes formation, and according to Whitman College Professor of Geology Patrick K. Spencer, there's nothing that would "suggest an organic origin" for this object, or any of the others found in the area because no vertebrate bones have ever been found at the site.
Similarly, George Mustoe has argued that this object (and others) may not be coprolites but are instead "pseudofossils created by mechanical deformation of plastic sediment." Natural causes that might mold sediment into a coprolite shape include "coseismic liquefaction, intrusion of sediment into hollow logs, or expulsion of sediment in response to gravity."