Late Triassic
Pant Quarry Fissure Fill
Bridgend, Glamorganshire, Wales.

Excellent 1mm tooth of one of the earliest mammals mounted on a standard microfossil slide.

Mammal.

Morganucodon is considered the earliest known mammal by many paleontologists while others contend it belongs to a group closely-related to early mammals.  Unlike most Mesozoic mammals, other parts of Morganucodon’s skeleton are known and there appears to be evidence it had fur and the females produced milk for their offspring which would qualify it as a mammal.

This is the kind of fossil many mammal collectors don’t consider largely because they don’t know it’s available. We think about mammoths and sabercats and early horses the size of a housecat but two-thirds of mammal evolution took place before the dinosaurs died out. It can be tough to find identified mammal teeth from the Mesozoic and this is as old as it gets.