Recently scientists discovered a clutch of 150-million-year-old fossil eggs that may be an important “missing link” in evolutionary history.(These were around long before there were chickens. The egg came first. )
An armoured jawless fish (a Cephalaspis, which is a kind of osteostracan). This creature evolved as it adapted to the transition from open sea to freshwater conditions in the Ludlow area towards the end of the Silurian. It had not evolved at the time the rocks beneath Whitcliffe were laid down, but fossils of the animal have been found in the younger rocks just to the east, downstream of Ludford Bridge.
Pradoella Calymenid Moroccan Trilobite; Trilobites Order Phacopida Suborder Calymenina, Superfamily Calymenoidea, Family Calymenidae; Geologic Age: Lower Ordovician; Trilobite is 150 mm long Draa Valley, Morocco; Remarks: Note the upturned rostrum that might have been used by the trilobite plow through the sea floor to scare up a meal.
The fossil comes from the Bellevue formation in Ohio. Image via Wiki Commons This is Streptaster vorticellatus, a member of the Edrioasteroidea class. It lived “only” 450 million years ago, during a period called the Ordovician. The body plan for this class was simple: a main body (theca), composed of many small plates, a peripheral rim for attachment, and (in some species) a pedunculate zone for extension and retraction.