On July 4, Jacob Bartlett asked "Why isn't the meadowlark grouped with the
Horned
Lark and the Sky Lark?"
The answer to this question is simple, but the factual basis underlying the
answer is complex. So I'll only give the simple answer here, which is that
comparative anatomical studies and molecular genetic comparisons show, beyond a
reasonable doubt, that both of our Meadowlark species belong to the New World
family Icteridae (grackles, blackbirds and orioles) and not to to the Old World
family Alaudidae (true larks), to which the Horned Lark and Skylark belong as
shown by those same criteria.
The reason our Meadowlark was given that name was based on a first impression:
it looks very similar to some of the true larks (called Longclaws) that live in
Africa. Here is what Wikipedia has to say about that
(http://en.wikipedia.org/wiki/Eastern_Meadowlark):
This species was first described by Carl Linnaeus in his 1758 Systema nature as
Alauda magna. The type locality [where the specimen he examined and described
came from] is mistakenly given as "America, Africa"
Linnaeus' error is explained by two facts: first, he did not distinguish
between the Eastern and Western meadowlarks. The peculiar belief that this bird
also occurred in Africa is due to confusion of the yellow-breasted meadowlarks
with certain longclaws (Macronyx), quite unrelated African songbirds.
Specifically the Cape Longclaw (M. capensis) and the Yellow-throated Longclaw
(M. croceus) share similar habitat and habits [and look quite similar to our
Meadowlarks]…."
Linnaeus recognized his error less than a decade later, separating the
longclaws from their meadowlark look-alikes.
Common names are not reliable indicators of evolutionary relationships. There
are many examples of this. The European Blackbird is closely related to the
American Robin (both are thrushes in the genus Turdus) and not to blackbirds.
The warblers in Europe, Africa and Asia are in an entirely different family
from the New World warbler families. If interested, you can read about the
problem of names versus relationships in a paper by Gill et al. (Wilson Journal
of Ornithology 121(3):649–652, 2009).
