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New Burnham Book
Wow. If this editorial review accurately reflects the content of the book then
Burnham really seems to be in Imaginationland. He seems to have dispensed with
even basic facts and evidence in favor of fun scenarios.
"Maniraptora includes the first known bird, Archaeopteryx, the small,
four-winged, feathered glider, Microraptor, and the terrestrial runner
Bambiraptor. All are considered important links in the origin of flight
and a subsequent transition to terrestriality. In cladistic
classifications, dromaeosaurid ?dinosaurs? were only considered
terrestrial cursors. "
-Here "were" is the operative word, as in during the seventies. However, Abel
considered them arboreal starting in 1911, and Witmer has always cited the
possibility of small arboreal dromaeosaurs since at least 1995. Moreover,
cladistics never "considered" a habitat preference, it only quantified degrees
of similarity between lineages.
"The discovery of a gliding stage within the
dromaeosaurs confounds the currently suggested evolutionary framework
and lacks predictability for origin of flight scenarios. "
-It in no way confounds any framework. In Hwang et al. the TWG cladogram placed
dromaeosaurs as diverging from troodontids after avialae did. And what
difference do scenarios make? Scenarios should change to fit new fossil
was a significant factor for evolution of dinosaur-like birds and
birdlike dinosaurs during the Mesozoic. This time is characterized by
faunal and floral changes reflecting the cooling trend at end of the
-Fascinating. How did the cooling at the end of the Cretaceous influence the
evolution of Jurassic animals like Archaeopteryx, Anchiornis, or Pedopenna?
There sure wasn't any cooling in the Jurassic. Perhaps there was a time
"The environment opened up making it difficult for poor
fliers and gliders as forested areas became less dense. Secondarily
flightless terrestrial forms and birds with full flight capabilities
survived best in these new environments. "
-Is there any paleobotanical evidence that forested areas became less dense in
the Jurassic or Cretaceous? I sure haven't seen it in any accounts of the
Yixian or Tiaojishan.
"Eventually, birds of modern
aspect probably replaced the primitive maniraptorans since they were
more efficient fliers and had evolved higher metabolic rates suitable
for the cooler climate."
-By "eventually" Burnham must mean "already", since carinate birds had already
diversified by the time of Microraptor.
I just really don't understand the approach of ignoring the fascinating new
evidence in favor of a barely tenable scenario.