The paper
M. Srivastava et al., "The Amphimedon queenslandica genome and the evolution of animal complexity," Nature, 466:720-26, 2010. Free F1000 Evaluation
The finding
The marine sponge Amphimedon queenslandica evolved from single-celled ancestors before the Cambrian explosion, making it one of the earliest multicellular organisms. However, when Bernard Degnan of The University of Queensland and colleagues analyzed the sponge’s genome, they saw that it shared genes that are characteristic of more complex animal traits, suggesting that these genes evolved before multicellularity itself.
The genes
The sponge carries genes that, in more complex animals, code for transcription factors involved in differentiation of muscles and nerves—despite not having a neuromuscular system itself. One theory proposes that Amphimedon is a “throwback,” having evolved to a simpler organism from a more complex ancestor, but according to Faculty Member Doug Erwin the new data do not support that point of view.
The descent
The presence ...
