For birders all over the world

DID DINOSAURS EVOLVE INTO BIRDS?
HOW A 140-YEAR MYSTERY WAS SOLVED

In 1842 Sir Richard Owen, the first director of The Natural History Museum, coined the name "Dinosaur" for a particular group of ancient reptiles. Since then these creatures have fascinated scientists and people of all ages. Dinosaurs dominated the Earth for millions of years, but what happened to them and where did they go? The fossil Archaeopteryx provided some intriguing evidence - triggering a 140-year investigation.

1861 The early bird gets the attention

In 1861 a German quarry worker finds the fossil of a small skeleton surrounded by the delicate impressions of feathers and gives it to the local doctor in settlement of his medical bill. After intense negotiations Sir Richard Owen buys the specimen for The Natural History Museum and publishes a full scientific description of Archaeopteryx lithographica, which he regards simply as an ancient long-tailed bird.

1868 Odd bird or missing link?

Thomas Henry Huxley, advocate and defender of Charles Darwin's recently published theory of evolution, studies the Archaeopteryx fossil. Noticing that Archaeopteryx is a very reptile-like bird he decides to look for a very bird-like reptile. The small dinosaur Compsognathus, part of a group called the theropods, provides his missing link.

1926 Which dinosaurs?

Gerhard Heilmann publishes The Origin of Birds, a systematic study of vertebrate anatomy and embryology in which he announces, "We can therefore with absolute certainty maintain that the birds have descended from the reptiles". Failing to find the forerunner of a wishbone for Compsognathus in the fossil record - something believed to be essential in a bird ancestor - he instead nominates the ancient reptile Euparkeria as the ancestor of birds.

1968 New dinosaur family

American palaeontologist John Ostrom discovers the remains of a new species of theropod, a pack-hunting, ground-dwelling dinosaur with a lethally sharp curved claw on each foot, which he names Deinonychus. He creates a new sub-group of theropods called dromaeosaurs, recognised by their slashing toe. Later he comes across an old misidentified fossil of an Archaeopteryx. While studying these animals he notices something very familiar...

1973 A new theory

Ostrom observes how similar Deinonychus's hips and wrists are to those of Archaeopteryx and publishes his evidence. He concludes that the two animals are more closely related to each other than to any other. For most palaeontologists the anatomical evidence provided by these unique features is convincing, but some scientists, ornithologists in particular, remain sceptical.

1995 The first Chinese discovery

Local farmers in Liaoning province, China, find fossilized birds in 124-million-year-old sediment. Scientists from The Geological Museum of China name them Confuciusornis. The new fossils are slightly more advanced than Archaeopteryx, with no long bony tail or toothed jaws but their wings still have separate fingers ending in claws.

1996 A new missing link?

One of the quarries in Liaoning province reveals Sinosauropteryx, unmistakably a small theropod dinosaur. Scientists note with excitement a fringe of "unbranched integumentary structures" or "fluff" preserved along its backbone. Some believe this fluff may be a primitive type of feathery covering, useful for insulation in such a small dinosaur.

1997 Feathers found

Caudipteryx and Protoarchaeopteryx dinosaur remains are found in the same Liaoning quarry, with feathers similar to the body feathers of modern birds. Both animals have wrists similar to Archaeopteryx. Protarchaeopteryx also has very long hands - which some believe may be a pre-adaptation for flight.

2001 Final "fuzzy" piece of the puzzle

The Liaoning quarries produce the most spectacular fossil yet - "Fuzzy raptor". This dinosaur's skeleton shows it to be a dromaeosaur, related to Deinonychus. What really excites scientists are the perfectly preserved soft, downy body feathers that surround the skeleton. This is the final crucial evidence needed to confirm the relationship between theropod dinosaurs and the birds in your garden - birds are living dinosaurs.