Challenging conventional evolutionary views: corals pass on mutations acquired during their lifetime to future generations

In a discovery that challenges a century of conventional wisdom on evolution, corals have been shown to pass somatic mutations -- changes in DNA sequences that occur in non-germ cells -- to their offspring

"For a trait, such as growth rate, to evolve, the genetic basis of the trait has to be passed down from generation to generation," said Iliana Baums, professor of biology at Penn State and leader of the research team

Since Darwin's time, our understanding of evolution has become increasingly detailed

"In most animals, germ cells separate from body cells early in development," said Kate Vasquez Kuntz, a graduate student at Penn State and co-lead author of the study

Corals can reproduce asexually (by budding and colony division) or sexually (by producing eggs and sperm cells)

"This type of uniparental reproduction makes it easier for us to look for potential somatic mutations in female corals and to identify them through Simplify the total number of genetic possibilities that may occur in offspring to keep track of them

The team genotyped samples -- using a high-resolution molecular tool called a microarray to study DNA differences between samples -- from a large Elkhorn coral colony that produced offspring from a single parent Samples were collected from 10 different locations in 1999, as well as samples from nearly 20,000 genetic locations in five adjacent communities

The team then looked at single-parent offspring from Elkhorn coral colonies and found that 50 percent of the somatic mutations were inherited

"Because corals are grown from genetically identical colonies of polyps, somatic mutations generated in one polyp can be exposed to the environment and screened for their utility without necessarily affecting the entire colony," Baums said

Inheritance of somatic mutations by animal offspring