As I peer into the crack in the bark of the tree, all I see is dark. My eyes adjust gradually, then suddenly the dark shapes coalesce. My heart jumps; there is an eye, peering out at me. In the fraction of time it takes for me to realise I am being stared down by a roosting bird, I am transported back to watching ‘Jurassic Park’ – the part where the dinosaur eyes up the victim before going in for the kill. My pulse slows with the reality that this is no velociraptor. Given the two hundred new bird boxes we are putting into the trees at the moment, I’d better get used to close encounters like this. We are hoping the boxes will provide more opportunities for birds to nest come the spring, increase the chance of chicks making it through to fledging.
I enjoy the birds that live in our wood. Their calls lift my spirit as I walk under the canopy, their chatter is soothing. Different birds have different dispositions, and their changing activities over the year makes up part of the character of the wood. Finding nests in the spring, watching chicks develop and grow is such a delight and a privilege. But I also enjoy birds for their history, for their evolutionary story.
It was back in 1863 that the story began to unfold. Richard Owen, who was then the superintendent of the Natural History department of the British Museum, described a fossil. It was a near complete specimen from the Solnhofen limestone in Germany. The fossil was that of a bird, but it showed many features associated with reptiles – clawed forelimbs and a long bony tail for example. We now call this bird Archaeopteryx lithographica, and the specimen Richard Owen described is now part of the collection of the Natural History Museum; it is in fact the most valuable fossil in their collection, though the doctor who sold it to the museum for £700 was said to have received it from a patient in payment for medical services. I went to see this specimen; what an amazing feeling to look down at the feathered imprints and bone structure that went on to make such an impact on the scientific community. To look on the rock in front of me was to look down the tunnel of history and it was hard to drag myself away from the threads of stories, all interconnected and interwoven in this discovery.
The obvious result of unearthing Archaeopteryx was the gradual realisation that the birds of today are direct ancestors of the dinosaurs, but a there was another spin-off of exceptional timing. In 1859, Darwin had published his Origin of Species. It predicted that there would be intermediate forms in the history of a species, a link showing how species had evolved from the ancestral form. Only four years later, such an intermediate form was described in Archaeopteryx, though Owen did not recognise it as such. It was Thomas Henry Huxley, one of Darwin’s most fervent supporters, who used Archaeopteryx to back up Darwin’s theory in 1868.
That birds have evolved from dinosaurs is such a fabulous fact, such an intriguing concept. I love that we have individuals of such distinguished ancestry flying round our wood. The exact sequence of how the birds evolved is still unfolding, the knowledge base is constantly changing as new fossils are unearthed and techniques developed. There is a general consensus however, that the origin of birds began with the theropod dinosaurs, the group of dinosaurs which include Tyrannosaurus Rex. Theropods were bipedal, carnivorous dinosaurs, and while no one is suggesting T. Rex is the ancestor of today’s birds, there were smaller, intelligent, fast moving pack hunters such as Deinonychus, feathered dinosaurs that lived around 115 million years ago, who are likely candidates.
Of course, it’s no surprise that birds can remind me of dinosaurs – the dinosaurs I have become used to seeing in films and documentary programs have been modelled, to a large extent, on birds. Birds are helping us interpret the dinosaur fossils and infer behaviour we would otherwise be unable to deduce. They are a link back into the Mesozoic.
As I walk up through the wood on a dim day of mist and damp, where water vapour hangs heavy in the air and sound is muffled, it is easy to feel unnerved as the birds move around me. The glimpse of an eye through the leaves, the rustle of an unseen forager, a flash of movement between the trees, calls made eerie by my apprehension. The wood feels primeval. At these times in particular, I feel close to the eye of the dinosaur.
Trees of Sanctuary 