杏吧原创

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I REMEMBER as a kid exploring a near-derelict building on a bit of land behind a row of shops and finding a bird鈥檚 nest on a dusty shelf, complete with squawking, alien-like chicks. I still remember the thrill of feeling I鈥檇 stumbled across a secret 鈥� but there was also an odd sense of intrusion, like I鈥檇 walked in on my mother getting dressed.

Both emotions are provoked by 鈥榮 beautiful images of birds鈥� nests. 鈥淲hen I hold these fragile structures in my gloved hands, all built with beak and claw, it makes me wonder at the instincts that formed them, embedded in DNA honed over millions of years,鈥� she says. Beals, who lives in San Francisco, photographed the nests from collections in museums around the US.

Perhaps one of the reasons that seeing a bird鈥檚 nest is such an intimate experience is that it is a peek into their genes. Just as geneticists can talk about the genes that contribute to eye colour, or height, for example, they can also imagine genes that influence things further afield, outside the immediate structure of the organism, like a spider鈥檚 web or a bird鈥檚 nest. This is the idea of the , as conceived by evolutionary biologist Richard Dawkins. Bowerbirds, for example, probably have genes for selecting coloured items to decorate their elaborate bowers. Seeing a bird鈥檚 nest gives you an idea about their genes, as well as their environment, in a similar way to how seeing someone鈥檚 house gives you an idea about their social background. So the nest of this (main picture), collected in Arizona in 1965, tells us that it used garbage to construct a home rather than natural materials.

Each bird has a unique take on nest building: top left, a opts for a bucket; mid-left, a and bottom left, .