40 | NewScientist | 1 June 2019I
T HAS been an icon of palaeontology for
over 150 years. Archaeopteryx’s discovery,
a few years after the publication of On the
Origin of Species, couldn’t have been better
timed. Charles Darwin’s theory predicted that
the fossil record should be full of transitional
forms, as one species gradually evolved into
another. Yet these missing links were, well,
missing. Then, the strange birdlike dinosaur
was unearthed – and instantly became a poster
child for evolution.
After all this time, you might think there is
little left to discover about the “first bird”.
In fact, much of its story has yet to be told.
Only this February it emerged that the
original fossil – a feather – was not what it
seemed. And in recent years, we have found
other contenders for the title of first bird.
Nevertheless, new insights into the origins
and lifestyle of Archaeopteryx reveal it to
be a real trailblazer, making an epic journey
over sea before settling on remote islands –
a trip that shaped its evolution in a way that
certainly would have intrigued Darwin.
The first Archaeopteryx skeleton was found
in Germany in 1861, close to – and shortly
after – the feather. It was about the size of
a crow, and headless. Only with the discovery
of a second skeleton, a decade later, did it
become clear that instead of a birdlike beak,
Archaeopteryx had a snout filled with teeth.
Eleven specimens have been found in total,although one vanished mysteriously in 1991
after the death of its owner. Those that remain
reveal an animal that lived about 150 million
years ago in what is now western Europe.
Other birdlike dinosaurs lived in China,
according to fossils unearthed since the 1990s.
Like Archaeopteryx and modern birds, they are
theropods, a group of dinosaurs with hollow
bones and three-toed limbs that include
tyrannosaurs and velociraptors. The oldest of
the Chinese fossils date from 160 million years
ago, and reveal an animal that had feathers but
probably couldn’t fly. The first creatures that
closely resemble modern birds – theropods
capable of flight and with beaks – date from
around 125 million years ago.
So Archaeopteryx was just one of several
early birdlike dinosaurs. But details of its story
are still emerging, and they shed new light on
its evolution. To understand how, we must
travel back 175 million years to when thesupercontinent Pangaea began to break apart.
An ocean called the Tethys pushed in from
the east, creating Laurasia in the north – a
combination of what are now North America,
Europe and Asia – and Gondwana in the south.
Much of Europe was flooded, forming an
inland sea with a couple of Madagascar-sized
islands in the east and smaller ones further
west. These remote western islands, known
as the Solnhofen archipelago, are where
Archaeopteryx lived.Flying start?
The islands were tropical, lying 500 kilometres
from the equator, and surrounded by coral
reefs. Artists’ impressions often show
Archaeopteryx flapping from tree to tree,
but that’s probably wrong, says Oliver
Rauhut of the Bavarian State Collections
of Palaeontology and Geology in Germany:The early bird
Archaeopteryx’s travels shaped its evolution in
an intriguing way, discovers Michael Marshall
The tropical islands
where Archaeopteryx
lived probably lacked
trees, despite many
artists’ impressionsFeatures