You twice erroneously describe the extinct woolly mammoth and American mastodon as ancient “ancestors” of today's elephants (see http://go.nature.com/q7fvk6 and http://go.nature.com/91a4zy).

They are actually fossil relatives of today's elephant species, as is made clear in the original research paper (N.Rohland et al. PLoS Biol. 8, e1000564; 2010) on which the two items report. With the extensive range of expertise at the disposal of your journal, I am surprised at these slips.