A new understanding of adaptive evolution, the way in which living things change and develop over many years to be able to live in a particular place, is emerging, thanks to an international team of scientists, led by the University of St Andrews.

Advances in biological science are leading to a striking new understanding of how organisms evolve. Natural selection is the  cornerstone concept in evolutionary biology, describing the process by which organisms better adapted to their environment tend to survive and reproduce, but which traits are favoured is partly determined by properties of the organism itself, leading to differences between species in the ability to evolve.

In a much-anticipated new book that lays out the new perspective, an international team of leading scientists describe how the evolutionary process has itself evolved over time. The team have summarised this new vision of evolution in a new book called 'Evolution Evolving', released today (Tuesday 24 September) by Princeton University Press.

First author, Kevin Lala, a Professor of Behavioural and Evolutionary Biology from the School of Biology at St Andrews explains:

"This is an exciting time for evolutionary biology. There have been many scientific discoveries recently that challenge the traditional understanding.  Phenomena that we used to think are impossible have been shown to happen, and that is making scientists think again."

The book describes how animals and plants adapt through cultural transmission, epigenetic inheritance or through their symbiotic bacteria. For instance, whales have cultural traditions that are driving genetic evolution, rats have been found to adapt to poisonous diets through exploiting the genes of bacteria they get by eating faeces and soil, and learned fears are reported to be inherited across generations through molecules that attach to DNA.

The perspective has already been endorsed by several leading biologists, including Harvard University's Professor Marc Kirschner who, while not among the authors, described Evolution Evolving as "a tour de force" and "a fascinating and original expansion of evolutionary theory", while Princeton University's Professor Agustin Fuentes described the book as "an eloquent, example-laden, accessible narrative setting the stage and offering the story of a truly contemporary evolutionary theory".

The new theory has major implications for understanding human evolution too. One of the authors,  Professor Marcus Feldman, an evolutionary geneticist at Stanford University in California, and member of the US National Academy of Sciences, explained:

"Humans don't evolve like mice or fruit flies. We interpret natural selection differently because we develop differently, interact with the world differently, and inherit selectable variation differently."