Editing Adaptive radiation (section)

====Hawaiian honeycreepers====
The [[Hawaiian honeycreeper]]s form a large, highly morphologically diverse species group of birds that began radiating in the early days of the Hawaiian archipelago. While today only 17 species are known to persist in Hawaii (3 more may or may not be extinct), there were more than 50 species prior to Polynesian colonization of the archipelago (between 18 and 21 species have gone extinct since the discovery of the islands by westerners). The Hawaiian honeycreepers are known for their beaks, which are specialized to satisfy a wide range of dietary needs: for example, the beak of the ʻakiapōlāʻau (''[[ʻAkiapolaʻau|Hemignathus wilsoni]]'') is characterized by a short, sharp lower mandible for scraping bark off of trees, and the much longer, curved upper mandible is used to probe the wood underneath for insects.<ref name="Weiner" /> Meanwhile, the ʻiʻiwi (''[[ʻIʻiwi|Drepanis coccinea]]'') has a very long curved beak for reaching nectar deep in ''[[Lobelia]]'' flowers.<ref name="Olsen" /> An entire clade of Hawaiian honeycreepers, the tribe [[Psittirostrini]], is composed of thick-billed, mostly seed-eating birds, like the Laysan finch (''[[Laysan finch|Telespiza cantans]]'').<ref name="Olsen" /> In at least some cases, similar morphologies and behaviors appear to have evolved convergently among the Hawaiian honeycreepers; for example, the short, pointed beaks of ''[[Loxops]]'' and ''[[ʻAkikiki|Oreomystis]]'' evolved separately despite once forming the justification for lumping the two genera together.<ref name="Reding" /> The Hawaiian honeycreepers are believed to have descended from a single common ancestor some 15 to 20 million years ago, though estimates range as low as 3.5 million years.<ref name="Baldwin">{{cite journal|last1=Baldwin|first1=Bruce G.|last2=Sanderson|first2=Michael J.|year=1998|title=Age and rate of diversification of the Hawaiian silversword alliance (Compositae)|journal=Proceedings of the National Academy of Sciences|volume=95|issue=16|pages=9402–9406|bibcode=1998PNAS...95.9402B|doi=10.1073/pnas.95.16.9402|pmid=9689092|pmc=21350|doi-access=free}}</ref>