December 19, 2014 | David F. Coppedge

Birds Go Splat on Evolutionary Theories

A flock of surprising traits of birds has dropped a load on simplistic notions of evolution.

Birds evolved from apes:  How else can one explain the fact that “Crows join human, apes and monkeys in exhibiting advanced relational thinking“? (PhysOrg). A paper in Current Biology finds, “Such robust and uninstructed relational matching behavior represents the most convincing evidence yet of analogical reasoning in a nonprimate species” that is comparable to that of apes.  The scientists speculate that the findings are “perhaps representing a case of convergent evolution” of brain structures, but that’s all they want to speculate about how this “remarkable” capability that “excelled” at a task might have evolved:

Just how that remarkable transfer is accomplished represents an intriguing matter for future study. Nor are we claiming that crows will prove to be the only nonprimate animals that are capable of exhibiting such spontaneous relational matching behavior. Future research must be undertaken in which different species are given comparable pretraining experience to our crows. Until such systematic comparative research is conducted, it would be premature to offer speculative evolutionary accounts as to why crows appear to have excelled in solving this challenging cognitive task.

“Crows are smarter than you think,” says a press release from the University of Iowa; they “join humans, apes, and monkeys in exhibiting advanced relational thinking.

Amazing FactsBirds forecast tornadoes:  Why did a flock of golden-winged warblers evacuate days before a devastating storm system hit Tennessee?  Could they hear it coming in low-frequency vibrations?  A population biologist from the University of Minnesota was “blown away” by this hypothesis, which has never before been documented in birds, says National Geographic.  “It shows that the birds can do more than we give them credit for.”  Sensing distant tornadoes sweeping across the Great Plains, the birds flew the coop from their traditional nesting grounds.  PhysOrg says that infrasound may be the birds’ “early warning system.”  The storms in April spun off 84 tornadoes and killed 35 people.  When the storms retreated, the birds came back, having flown 900 miles round trip for safety.  “We thought the birds were just hunkering down,” the biologist said.  “It never occurred to me that they might have evacuated.”  Science Daily found a way to insert the phrase “climate change” into the story.

A boy is a rat is a cockroach is a bird:  A story on PhysOrg has this long headline: “Brain structures devoted to learning, memory highly conserved in animal kingdom, suggesting common evolutionary origin.” The article says that insects, birds, and humans all have common features in the way memory is organized, according to a survey by neuroscientists at the University of Arizona. Actually, this is not expected in evolutionary theory; any common ancestor of such widely divergent animals must have been much simpler, Darwin would say. “The correspondence across disparate groups of animals is extraordinary,” one of them said. “It’s almost too good to be true.

Hold your feathers, dino:  There was a bit of a flap in Science Magazine this week about feather origins.  Gerald Mayr, a museum official in Frankfurt, disputes an October 2014 paper that claimed feathers evolved first for display on dinosaurs.  “Hypotheses for their evolution in a nonaerodynamic context are therefore not only evolutionarily implausible but also not necessary to explain their origin,” he argues; feathers are for flying.  The German authors of the original paper defended their claim point by point.  “We emphasize that feathers did not ‘evolve for’ something; rather, their fortuitous [i.e., chance] appearance was associated with a selective advantage, which resulted in their retention.”  None of them explained how powered flight evolved in any detailed Darwinian way.  Interestingly, both appealed to Ken Dial’s 2003 WAIR hypothesis for the origin of flight (see 6/25/14).  If a better theory came about in the past 11 years, one would think they would cite it instead.

Update 12/19/14: Birds build snow tunnels for funNew Scientist asks why redpolls in Maine dig long tunnels under the snow, but suggests it might just be like play in the winter wonderland for them.  When one starts, others join the fun.  Perhaps it insulates them from the cold outside, too, but the two purposes are not incompatible.

Do you notice something tricky about evolutionary theory?—almost, one might say, magical?  Traits just “appear,” then Darwin comes in to “select” them.  In this case, advanced relational thinking appeared in crows.  Infrasound processing appeared in warblers.  Brain structures appeared in insects, birds and mammals.  Feathers made “their fortuitous appearance” in dinosaurs.  No explanation is given for their sudden, dramatic appearance out of the darkness, but then Darwin takes credit.  See our 8/24/07 commentary for the double entendre in the phrase, “evolution takes credit.”


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