Palaeontology: Giants unearthed
Xu Xing revels in an enthusiast's tour of the Mesozoic era and its denizens.
My Beloved Brontosaurus: On the Road with Old Bones, New Science, and Our Favorite Dinosaurs
By Brian Switek
Scientific American: 2013. 272 pp. $26
9780374135065
Brian
Switek is a science writer with a deep understanding and broad
knowledge of evolution. His books offer a compelling mixture of reliable
information, personal experiences and thoughts, anecdotes about
palaeontological research and even science philosophy, delivered in a
breezy and engaging style.
Sculptor Brian Cooley's reconstruction of a Tyrannosaurus rex. Image: REUTERS
In My Beloved Brontosaurus,
Switek — a fan of dinosaurs since childhood — describes his tours of
famous excavation sites, selected museums and high-tech research
laboratories across the United States. He meets and talks to a host of
palaeontologists, including fossil-bone expert Mark Goodwin at the
University of California Museum of Paleontology at Berkeley. By getting
close to the people and the science that they move forward, Switek
paints a comprehensive picture of how our understanding of dinosaur
evolution gradually advances. Along the way, he shows how dinosaur
palaeontology is a cultural touchstone in the United States and many
other countries.
Switek
touches on widely discussed topics, such as how dinosaurs rose to
dominance early in the Mesozoic era (250 million to 65 million years
ago) and why all of them — except the strange feathered ones we know as
birds — died out when the era ended. But his focus is on how dinosaurs
lived.
Switek picks through recently discovered fossils such as the carnivorous feathered dinosaur Sciurumimus albersdoerferi
found in Germany in 2011. And he discusses cutting-edge methods such as
the use of computed tomography scanning to investigate fossils' nasal
passages, brain cavities and other internal cranial features. A
recurring theme of the book is that new specimens, technologies and
thinking are making it possible to investigate how dinosaurs mated,
matured and became gigantic; to study their social life and the diseases
that afflicted some individuals; and even, as in the case of the small,
bird-like Anchiornis, to reconstruct aspects of their coloration.
Some
of Switek's best palaeontological stories come from the history of the
discipline. He explains how his favourite dinosaur when he was a child
was popularly known as brontosaurus, but had in fact been known
scientifically as Apatosaurus since 1903, when it was
reclassified as a species of the latter genus. Eventually, the new name
filtered through to museum exhibits and popular books, and although
brontosaurus may not have disappeared entirely, the current generation
of dinosaur-savvy children are aware of its obsolescence.
More often, Switek focuses on recent advances. The rediscovery of an animal called Effigia
in an old collection of fossils at the American Museum of Natural
History in New York helped researchers to show that some early relatives
of crocodilians were similar to many dinosaurs — not only did they have
a near-vertical rather than sprawling hindlimb posture, but they were
also bipedal. A reluctant field decision to break the thigh bone of a Tyrannosaurus rex
for ease of transport exposed a type of bone tissue seen today in
female birds that are about to lay eggs, revealing the dinosaur's
gender. And a graduate student's thesis research on the ink sacs of a
fossil squid led to a method for partially reconstructing the colours of
some extinct animals, including dinosaurs.
I
have a few quibbles. In some instances, Switek recounts a conversation
he had with a scientist to lend authority to an account of a discovery,
but the details on how inferences were made and hypotheses tested are
left out. The phylogeny-based definitions given for some animal groups
are slightly inaccurate, and there are occasional lapses in the
reliability of the scientific storytelling. For example, in discussing
the importance of Effigia, Switek glosses over the fact that
near-vertical hindlimb posture (although not bipedality) was already
known to be widespread among early members of the crocodilian lineage.
The
book largely revolves around the dinosaur stars from the early days of
North American palaeontology, and space for recent discoveries made by
researchers elsewhere is limited. Similarly, some fascinating new
research directions are discussed briefly or not at all.
Switek does not mention the 34 juveniles of the small, parrot-beaked dinosaur Psittacosaurus
that were found preserved with an adult in Chinese strata — a fossil
that is among the best evidence to support the existence of parenting in
dinosaurs. He also omits the use of isotopic analysis to reconstruct
the lifestyle of the mysterious spinosaurs — massive carnivorous
dinosaurs with vaguely crocodile-like heads. Nor is there anything about
molecular studies on the development of feathers, fingers and toes in
modern taxa, which have contributed greatly to our understanding of the
morphological evolution of birds.
Of
course, not even a brontosaurus-sized book could include everything.
Switek has succeeded in covering a wide range of interesting topics in
dinosaur palaeontology with infectious enthusiasm.
Author information
Affiliations
Xu Xing is professor in the Institute of Vertebrate Paleontology and Paleoanthropology of the Chinese Academy of Sciences in Beijing.
- Xu Xing
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