What sets Vilesida apart, however, is its chemistry. The sponges produce unusual sterols, organic compounds known for their ability to lower ‘bad’ LDL cholesterol – specifically 24-isopropylcholesterols – as major components of their cell membranes. These sterols mirror fossil biomarkers found in Ediacaran rocks older than 600 million years, long suspected to indicate early animal life.
“These sterols are a perfect match with the oldest known animal biomarkers,” explains Paco Cárdenas, curator at the Museum of Evolution and senior author of the study. “Our results strengthen the sponge biomarker hypothesis, suggesting sponges – and therefore animals – originated far earlier than previously believed.”
This emerging picture aligns with a recent PNAS paper by members of the same research team, which also tied ancient sterol signatures to early sponges.
The implications of the Vilesida discovery reach beyond evolutionary timelines. Sterols of the type produced by the new sponge order have already drawn attention for their pharmaceutical potential, with past studies highlighting antimicrobial, anticancer, and antiviral properties.
“Now that we’ve named these sponges and mapped their habitats, chemists and pharmacists can more readily pursue these compounds,” Cárdenas notes. “Vilesida may prove as medically valuable as it is evolutionarily significant.”
As researchers continue to unravel the molecular and ecological roles of the new order, Vilesida stands poised to redefine not only sponge biology, but perhaps the very origins of animal life in Earth’s oceans.