TEHRAN (FNA)- The 160 million-year-old fossil of an extinct rodent-like creature from China is helping to explain how multituberculates -- the most evolutionarily successful and long-lived mammalian lineage in the fossil record -- achieved their dominance.
The nearly complete skeleton provides critical insights into the traits that helped such multituberculates thrive in their day.
London, March 15 ( ANI ): Scientists have revealed that rodent-like creatures called multituberculates, flourished during the last 20 million years of the dinosaurs' reign and survived their extinction 66 million years ago.
A new research led by a University of Washington paleontologist suggests that the multituberculates did so well in part because they developed numerous tubercles (bumps, or cusps) on their back teeth that allowed them to feed largely on angiosperms, flowering plants that were just becoming commonplace.
The Multituberculates are an extinct lineage of mammal, which had their first appearance in the Jurassic, are common in the early Tertiary and become extinct in the middle Chadronian (4).
DISCUSSION All of the identifiable multituberculates that have been reported from post-Bridgerian rocks have been assigned to Ectypodus and nothing in our sample suggests a different genus.
Chief among these early mammals was an order called the multituberculates, a tongue-twisting name that paleontologists often shorten to multis.
Despite their evolutionary endurance record and their wide diversity of species, multituberculates have remained an enigma, even after a century of study.
Tubules have been noted in a wide variety of taxa, occurring extensively in marsupials and multituberculates
and to a lesser degree in bats, primates, and rodents (Sahni, 1985).
The mammals are most likely multituberculates
, an extinct order of archaic mammals that resemble rodents and had paired upper and lower incisors - which they used to gnaw at the bones for minerals rather than for meat.
The multituberculates, a diverse and well-represented group of mammals that first appeared in the late Jurassic of North America (Van Valen & Sloan, 1966; Carroll, 1988), were very likely the earliest nut-dispersing mammals.
The fossil record indicates that first multituberculates and later ischyromyids, squirrels, and mice have coexisted with nut-bearing plants and their ancestors since the Cretaceous, and it appears that these plants and animals may have had strong effects on each other's evolutionary histories.