What came first – the chicken’s egg or the dinosaur’s?

Infinite Life Jules Howard Elliott and Thompson £20

In New Guinea there is a creature only discovered by Western science in 1961. It has been named ‘Sir David’s long-beaked echidna’ to honour national treasure Sir David Attenborough. Zaglossus attenboroughi, as it is formally known, is one of only five living monotremes, mammals that lay eggs. Echidna eggs are about the size of a marble, those of its fellow monotreme, the platypus, a large pea.

The egg, Howard writes, is ‘the most unifying, resilient life structure that Earth has ever cooked up’. Its evolutionary history dates back hundreds of millions of years.

Mention eggs today and most of us think of birds. However, dinosaurs also laid eggs. This was not always thought to be so. Paleontologists in the 19th century and even later speculated that dinosaurs gave birth like mammals. It was only in the 1920s that the American explorer Roy Chapman Andrews, sometimes cited as the inspiration for Indiana Jones, found what were indisputably dinosaur eggs in the deserts of Mongolia.

Like many birds’ eggs, dinosaur eggs were probably coloured. Those of velociraptors may well have been speckled, dusted with spots. And, like birds, dinosaurs most likely sat on their eggs to protect them and maintain the right conditions for growth.

However, in his search for the ‘true history of the egg’, Howard ventures far further into the past. The earliest evidence for the existence of eggs can be found in fossils from 600 million years ago. The creatures that produced them may have resembled jellyfish, and their eggs would have been ‘the size of a full stop, sometimes less than the width of a human hair’.

Howard unearths some real horror stories. A mere 250 million years ago, he locates the origins of parasitic insects. In his words, there has been ‘no more chilling egg-layer in the history of our planet than the earliest parasitoid wasps’.

Today, the emerald cockroach wasp has a sting that, effectively, turns cockroachs into zombies. Charles Darwin was so appalled by such creatures that their existence shook whatever religious faith he had. ‘I cannot persuade myself that a beneficent and omnipotent God would have designedly created parasitic wasps.’

In a book that brilliantly evokes past eras, Howard provides a new perspective on the history of life on Earth. As he puts it, ‘Each egg has its own charisma, allure and evolutionary back story, easily… as diverse and interesting as the animals that hatch out of them.’ And he proves his case eloquently.