An international effort mapped out thousands of physical traits and genetic clues to trace the lineage of placental mammals – a big group of animals with more than 5,000 species that includes cats, whales, elephants and humans – and the creature that gave rise to all of us has at last been pinpointed.
It’s a small, furry, insect-eating animal that lived just 200,000 years after the extinction event that saw the end of the dinosaurs.
This research tackles the question of placental mammals in unprecedented detail. The team gathered more than 4,500 details of phenotype – diet, lengths of limbs, shapes of teeth, length of fur if any, and so on – from 86 different species that are around today, and from 40 fossils of extinct animals in six years and taking a decidedly modern take on it.
“Anatomy and research in palaeontology had a very 19th Century veneer to it – that we would sit in small groups in a lab with a fossil describing it,” said lead author of the study Maureen O’Leary of Stony Brook University in New York, US. “That is a very effective and important part of what we do, but by trying to bring this into the 21st Century and using new software, we were able to really band together as a group of experts and tackle a much larger problem,” she told BBC News.
To this database, they added 12,000 detailed images and genetic information for those species, channeling all the data into what Dr O’Leary called “a supermatrix – essentially like a spreadsheet, filled with observations and images, to create a really rich description of mammals we’d sampled” and working on it with the help of a newly developed software named Morphobank.
The team also incorporated them into an artist’s conception of what it would have looked like.
Great work, guys.