Tullis Onstott (January 12, 1955 – October 19, 2021) was a professor of geosciences at Princeton University who has done research into endolithic life deep under the Earth's surface.
In 2011 he co-discovered Halicephalobus mephisto, a nematode worm living 0.9–3.6 km (0.56–2.24 mi) under the ground,[2] the deepest multicellular organism known to science.
He won a LExEN Award for his work "A Window Into the Extreme Environment of Deep Subsurface Microbial Communities: Witwatersrand Deep Microbiology Project".
[3] In 2007, Onstott was listed among Time Magazine's 100 most influential people in the world.
[5] After receiving his doctoral degree, Onstott, spent the next three years as a postdoctoral fellow in Derek York's laboratory at the University of Toronto performing research involving 40Ar/39Ar geochronology, before returning to Princeton as a professor.