Date: 1/12/18 12:38 pm
From: Robert O'Brien <baro...>
Subject: [obol] Re: Brown Creeper (Certhia americana) phylogeny
Oh boy. Them's fightin' words....................

What I meant to say is that Brown Creeper is about the closest thing* _we
have here_*
to a woodpecker. Of course, my statement was more general than that, but
I'll still defend it.
If there is something closer in Oregon/US to woodpeckers I want to learn
what it is.

We don't have a whole lot of trunk-feeding birds here. Off the top of my
head we have woodpeckers,
creepers, and nuthatches. (Tits, kinglets, some warblers and maybe some
others sometimes feed in trunk crevices
but not habitually). Woodpeckers and creepers have stiffened, elongated
central feathers
(as the roosting photo shows). These are used in balancing these two
families for their lives
against vertical or flat surfaces, often or always against tree trunks.
they roost in a similar fashion.
Nuthatches do not have such tail feathers. I'm not sure where they roost.

Woodpeckers have heads/bills adapted to pounding into softer wood while
don't. Woodpeckers usually have two toes forward and two behind while
creepers have the usual
3:1 structure. Yet woodpeckers, especially the smaller ones, feed very
often in bark crevices just as creepers do.
While creepers don't excavate true holes as woodpeckers often do, they
usually nest along tree trunks
as well; usually under pieces of loose bark, but are not above nesting in
existing cavities of a sort and even clean
them out of debris or loose/rotted wood as woodpeckers do.

I didn't say they were phylogenetic (direct) descendents of woodpeckers or
a common ancestor.
There is evolution, and there is *_convergent evolution_* of which I
claimed the latter.
That is, they have evolved from different original families to occupy a
similar habitat and lifestyle
to another family's descendents. (Cacti & euphorbias are totally unrelated
family-wise, but
have evolved similar structures and habitats (succulent, drought tolerant,
thorns, supressed or absent leaves, etc.).
Their different upbringing is given away by their totally different
flowers, however.)

Another example. Australia has no woodpeckers at all. The closest thing
that continent has is Riflebirds,
specifically in my experience, Paradise Riflebird, a flicker-sized bird
with a (very strong in this case)
decurved bill like Brown Creeper's miniature bill. It lacks the central,
stiff tail feathers, it's tail more like
a nuthatch. Like Creepers, this species has no phylogenetic relationship
to woodpeckers but has
evolved similar habits such as foraging in rotting wood.

The Wallcreeper of Eurasia has a similar clinging lifestyle as their name
implies, but they also
lack the central tail feathers with tails like nuthatches to which they are
sometimes thought to be
related. They're still working on evolving that feature I guess. They
have no plans to
evolve bills capable to boring into rocky cliffs, their preferred habitat.

So there (hee, hee; how do ya' like them apples?).


On Fri, Jan 12, 2018 at 10:33 AM, Nathaniel Wander <nw105...>

> While I’m guessing that Bob O’Brien offered the remark that Brown Creepers
> were the “about the closest thing that you can get to a woodpecker” in an
> act of kindness to lighten the mood and “spare the blushes” of an honest
> mis-identification, they are, of course, nothing of the sort. Creepers
> (treecreepers in the Old World) are songbirds: they don’t look like
> woodpeckers, they don’t behave like woodpeckers and they have no near
> phylogenetic relationship to woodpeckers. Their one interesting connection
> to woodpeckers is that they compete with and defend territories against
> Redheaded Woodpeckers (*Melanerpes erythrocephalus*) in eastern North
> America. Even still, they prefer arachnids to insects and eat seeds in
> winter.
> Brown Creepers’ closest relatives are the as many as ten treecreeper
> species in Europe and Asia. After that, they appear to be most closely
> related to gnatcatchers and are considered general kin to wrens—these
> species comprise the family Certhioidea. There are thought to be about six
> to nine races of Brown Creepers in North America, not counting a few
> Mexican races that reach the mountains of Arizona and New Mexico. The
> details of their relationships have been much debated. In the past the
> North American birds have sometimes been divided into three or four
> discrete species, sometimes even lumped with the Eurasian Treecreeper (*C
> familiaris*). There was a proposal before the AOS last spring to divide
> the present single New World species into a North American species
> (exclusive of the highland Arizona/New Mexico populations) and a
> Mexican/Central American species (including highland Arizona/New Mexico
> populations) possibly to be named Nearctic Creeper and Neotropical Creeper
> respectively. I can’t see that it has been voted on yet.
> Otherwise, creepers feed on tree trunks by poking beneath bark flakes
> rather than boring holes like woodpeckers. They are not cavity nesters,
> but weavers. They communicate via high pitched calls and songs, not
> drumming and they are cryptically colored rather than boldly marked. They
> take insects but prefer arachnids and, of course, their prey range is
> generally significantly smaller than that of woodpeckers: I’ve found no
> evidence that they consume ants.
> It may be that Bob wasn’t genially joking, but was thinking of
> woodcreepers (Dendrocolaptinae) rather than creepers/treecreepers. These
> 50-60 odd Central/S American forest birds fall in the woodpecker size range
> and have some evolutionarily convergent features with the latter including
> stiff tails which they use woodpecker-like as an important point of contact
> in shimmying up tree trunks. Woodcreepers generally have heavy bills, but
> use them for bark-probing like creepers/treecreepers rather than boring
> like woodpeckers. Their generally cryptic coloration is also sometimes
> said to be convergent with creepers/treecreepers. Woodcreepers too are
> passerines, though suboscines (like flycatchers) rather than ‘true’ oscine
> songbirds. Suboscine songs are generally less complex than those of oscine
> songbirds and typically are acquired genetically rather than learned.
> Nathaniel Wander
> Portland, OR
> *Max Planck* is supposed to have said:
> A new scientific truth does not triumph by convincing its opponents and
> making them see the light, but rather because its opponents
> eventually die
> and a new generation grows up that is familiar with it.
> *Andreas Wagner* observed of Planck's remark:
> Science, like nature, advances one funeral at a time. (*Arrival of the
> Fittest*, p.197)

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