Evolutionary anachronism is a concept in evolutionary biology, named by Connie C. Barlow in her book The Ghosts of Evolution (2000), to refer to attributes of living species that are best explained as a result of having been favorably selected in the past due to coevolution with other biological species that have since become extinct. When this context is removed, the said attributes appear as unexplained energy investments on the part of the living organism, with no apparent benefit extracted from them, and perhaps are prejudicial to the continued reproduction of the surviving species.