Mankind may be descended from apes but Australian scientists have found proof of links much closer to the sea floor, with a study revealing that sea sponges share almost 70 percent of human genes.
Genetic sequencing of sea sponges from the World Heritage-listed Great Barrier Reef showed the ancient marine animal shared many of its genes with humans, including a large number typically associated with disease and cancer.
Lead researcher Bernard Degnan, of the University of Queensland, said the findings "would shed light on a whole range of different things," and could lay the foundation for breakthroughs in cancer and stem cell research.
"Sponges have what's (considered) the 'Holy Grail' of stem cells," Degnan told AFP.
Exploring the genetic function of sponge stem cells could provide "deep and important connections" to the genes that influenced human stem cell biology, he said.
"(It) might actually inform the way we think about our own stem cells and how we might be able to use them in future medical applications," he said.
The study -- published in the journal "Nature" this week -- is the result of more than five years of research by an international team of scientists.
It required the extraction of "really pure DNA" from sponge embryos and a complex sequencing exercise, Degnan said.