Biology:Physeterula

Physeterula was a prehistoric close relative of the sperm whale that lived in Europe and the United States during the Late Miocene-Early Pleistocene.

Description

This large species is the most stemward physeterid, retaining functional upper teeth lacking enamel. In large specimens, tooth dimensions included total heights reaching up to 13.5 cm (0.44 ft). cm and mid-root diameters around 2.4~2.7. cm, reflecting a structure suited to the animal's predatory lifestyle while being smaller and finer than the massive, combat-oriented teeth of extant Physeter.

Body length estimates for adult Physeterula are approximately 5–6 meters (16–20 ft) long, based on skull dimensions exceeding approximately 1.4 meters (4.6 ft) in condylobasal length, isolated vertebrae, and comparative ratios from related Physeteroidea like Orycterocetus and Physeter macrocephalus, consistent with its position as a small to mid-sized basal Physeteridae. Based on the discovery of large individuals in fossil findings of Physeterula found in the North Sea, it is possible that it grew up to about 9–10 meters (30–33 ft).

Paleobiology

The presence of functional upper teeth is similar to Macroraptorial sperm whales such as Livyathan. and brygmophyseter. However, since the upper teeth lacked enamel and were thin and pointed, it is unlikely that they hunted large prey. The diet of Physeterula likely included soft-bodied prey, as inferred from tooth wear patterns showing anterior abrasion and slender, enamel-less teeth measuring 91.5-135 mm in length. Recent studies of tooth growth bands suggest rapid growth and a short lifespan, consistent with a predatory lifestyle targeting mobile prey. Physeterula diet would have been limited to cephalopods and fish.This is a diet similar to that of a modern Physeter macrocephalus, it would also have used a feeding method between that of primitive Physeteroidea and modern Physeter macrocephalus.

References

Template:Odontoceti Wikidata ☰ Q7189536 entry