Today is National Fossil Day, which calls attention to the incredible Earthly secrets that can be revealed through the study of ancient bones. This year held a number of fascinating fossil finds; here is a roundup of some of the most recent discoveries.
Ancient Kangaroos Walked Step-By-Step
Researchers have released a paper revealing that a 10,000-year-old kangaroo had an interesting gait, and just in time to celebrate National Fossil Day.
A statistical and biomechanical analysis of ancient kangaroos and their ancestors suggests some early species, such as stheneurines, were bipedal walkers instead of hoppers, Brown University reported.
The sthenurines had an anatomy that would have made them poor jumpers, especially because of the fact that some of them weighed up to 550 pounds.
"I don't think they could have gotten that large unless they were walking," said Christine Janis, professor of ecology and evolutionary biology at Brown University.
Sthenurines had proportionally bigger hip and knee joints than modern kangaroos, as well as a differently-shaped pelvis allowing for larger gluteal muscles. These muscles would have allowed the ancient kangaroo ancestors to balance their weight on just one leg at a time. An inflexible spine also suggests pentapedal motion would have been difficult.
"If it is not possible in terms of biomechanics to hop at very slow speeds, particularly if you are a big animal, and you cannot easily do pentapedal locomotion, then what do you have left?" Janis said. "You've got to move somehow."
The findings were published in a recent edition of the journal PLOS ONE.
Earliest-Known Lamprey Larva
Yesterday scientists revealed the discovery of the earliest-known lamprey larva.
The researchers were surprised to find this 125 million-year-old specimen was almost identical to its modern "cousins," the University of Kansas reported. Lampreys have seven pairs of gill arches that may have evolved into human jaws and even inner ear bones.
"Among animals with backbones, everything, including us, evolved from jawless fishes," said Desui Miao, University of Kansas Biodiversity Institute collection manager. "To understand the whole arc of vertebrate evolution, we need to know these animals. The biology of the lamprey holds a molecular clock to date when many evolutionary events occurred."
Meat-Eating Dinosaur From A Volcanically-Active Time Period
Earlier this month researchers released the discovery of an early Tyrannosaurus rex relative that walked Venezuela right after the mass extinction that ended the Triassic phase.
So far only two bones from the dinosaur's lower leg have been found, but it is believed to have stood about five feet tall, Science AAS reported.
"These survivors of the Triassic-Jurassic mass extinction were the 'ground zero' for later theropod evolution," Thomas Holtz Jr., a vertebrate paleontologist at the University of Maryland, College Park, who was not involved in the study told Science AAS. "[The new study] shows that important discoveries don't have to be of the biggest or the scariest [dinosaurs]."
Fossil Reveals Secrets Of Earliest Multicellularity
A 600-million-year-old fossil suggests multicellularity appeared about 60 million years before the first skeletal animals walked the Earth, which contradicts past ideas of the evolution of the earliest creatures.
The finding provides insight into when solo cells started working together to create life forms, Virginia Tech reported.
"Fossils similar to these have been interpreted as bacteria, single-cell eukaryotes, algae, and transitional forms related to modern animals such as sponges, sea anemones, or bilaterally symmetrical animals. This paper lets us put aside some of those interpretations," said Shuhai Xiao, a professor of geobiology in the Virginia Tech College of Science
Biggest Snout In Ancient Utah
Researchers discovered a plant-eating duck-billed dinosaur, dubbed the "Nose King," that lived in what is now Utah 75 million years ago.
The dinosaur was believed to be about 30 feet long and weighed over 8,500 pounds. Researchers are still not sure what the dinosaur's giant snout was used for, but have some tentative ideas, North Carolina State University reported.
"The purpose of such a big nose is still a mystery. If this dinosaur is anything like its relatives then it likely did not have a super sense of smell; but maybe the nose was used as a means of attracting mates, recognizing members of its species, or even as a large attachment for a plant-smashing beak. We are already sniffing out answers to these questions," said Terry Gates, a joint postdoctoral researcher with North Carolina State and the North Carolina Museum of Natural Sciences.
First Dinosaur That Hunted On Both Land And Sea
In September researchers discovered what is believed to be the first example of a semiaquatic dinosaur.
The Cretaceous-era predator is believed to have adapted to aquatic life about 95 million years ago, the National Geographic Society reported. The giant creature was about nine feet longer than the Tyrannosaurus rex.
"Working on this animal was like studying an alien from outer space; it's unlike any other dinosaur I have ever seen," said lead author Nizar Ibrahim, a 2014 National Geographic Emerging Explorer.
