Otherlands author Thomas Halliday: ‘Some people have insisted on reading the book backwards’

Thomas Halliday was born in 1989 and raised in Rannoch in the Scottish Highlands. He studied zoology at Cambridge before specialising in paleobiology for his master’s and PhD – winning the Linnean Society Medal for the best doctorate in biological studies. His debut book Otherlands: A World in the Making – which comes out in paperback on 2 February – was Foyles’ nonfiction book of 2022, while the historian Tom Holland called it “the best book on the history of life on Earth I have ever read”. Halliday lives in north London with his wife and sons.

What is paleobiology?
In the late 20th century, we began to realise that we could study far more aspects of past life than simply describing the forms and defining them into taxonomies. Paleobiology encompasses everything from cell biology to genetic relationships to ecology. It’s like any other part of biology, except it happens to be set in the deep past.

Where did the idea for Otherlands come from?
One thing that led to it was the idea that when we think about organisms in the past, we tend to talk about them in a family-tree sense, but never stop to think about what is going on in any given slice through time. A few years ago I entered the Hugh Miller writing competition and wrote about some of the earliest four-limbed vertebrates to come on to the land, which had been found in south-east Scotland. When it won, I thought: maybe I can turn that approach into something longer form.

It’s quite a challenge, distilling 550m years of natural history into 300 pages. How did you go about it?
The idea of having one chapter for each geological division of time came fairly early on. I wanted to make sure that I covered not just the vertebrates that get done over and over – the dinosaurs and the ice age mammals – but a variety of places and times and environments. The difficulties came in making sure I had a global representation of sites. Africa is the least well-studied continent in terms of palaeontology, but there are sites there which are phenomenally interesting.

You bring each site to life very vividly, no matter how alien its flora and fauna seem to us now.
I wanted to avoid writing things like, “In 1974, so-and-so did this study”, which is a useful form of science communication, but when I’m trying to evoke a place, it really takes you out of it. So there are almost no references to people at all – and that includes me or the reader. You can read it as if you’re there. It’s purely descriptive of the place. I was inspired by a lot of nature and travel writing, particularly books like John Lewis-Stempel’s Meadowland, Adam Nicolson’s The Seabird’s Cry or Robert Macfarlane’s Underland – books that really give a sense of place.

Where do you write?
I don’t have a particular place that I need to be. A lot of Otherlands was written in Birmingham. I had to commute up from London for work and was spending two nights a week in a largely empty house, and writing was something to do to relax in the evenings. I also wrote on the train and in libraries. In our house there is no dedicated writing space. The table I often write at is also the table that, until recently, we were using for nappy changes. But I did very much enjoy writing at the British Library, because you have to leave everything else at the door. It’s a very good way of getting on without any distractions; you can’t suddenly disappear into the kitchen and have a snack.

What have you been reading lately?
I read Eoghan Daltun’s An Irish Atlantic Rainforest, which is absolutely fantastic, a paean to rewilding and the benefits of letting nature do what it does best. It’s an exploration of how much life there is just waiting under the soil to return. I really enjoyed Katherine Rundell’s The Golden Mole, a selection of essays about endangered species that is very evocative. I’ve just started Elderflora: A Modern History of Ancient Trees by Jared Farmer, and it’s very interesting so far. One novel I absolutely loved recently was The Binding by Bridget Collins, a fantasy book about bookbinding and magic.

Otherlands is teeming with literary references. Do you have a favourite piece of fiction that considers the pre-human world?
A lot of the works of fiction that deal with the past end up being a little bit too rough-and-tumble adventure-y for me. That’s why I didn’t refer to things like Arthur Conan Doyle’s The Lost World, where characters go in with guns and bring back specimens, or the likes of Jurassic Park where it’s all very bestial. There was quite an interesting book set in the deep past called Hawksbill Station by Robert Silverberg. The conceit is that humans have discovered one-way time travel into the past and the government is using it to send political dissidents back to the Cambrian period. It ends up being a really interesting story about your place in time and what makes it home, though it’s not really about the organisms that live there.

Otherlands came out in hardback a year ago. How have readers responded?
People’s responses to it going backwards in time have been really interesting. I arranged the chapters from most recent to oldest, purely for the purposes of easing the reader in, so we start off with organisms that are more familiar. But some people have insisted on reading the book backwards, so that it’s a story of the Earth in chronological order. Some said [going backwards in time] gave them a sense of decentring humans: we are there at the beginning, but then we’re gone and it’s no longer the story of Earth leading up to us. I really liked that interpretation. There was one person who said going back in time made it a happier experience, because if you learn about something being extinct in one chapter, then all of a sudden, in the next one, it’s alive and well.

• Otherlands by Thomas Halliday is published by Penguin (£10.99). To support the Guardian and Observer order your copy at guardianbookshop.com. Delivery charges may apply