This Week in Science (14/02/2025)
A wobbly planetary core and a dinosaur with sloth-like hands
A dynamic inner earth
Scientists have long known that Earth's inner core rotates at a different and variable speed compared to the planet itself. However, new research published in Nature Geoscience suggests that the core's shape is also changing. Seismologist John Vidale and his team analysed seismic signals from 168 pairs of nearly identical earthquakes to determine whether variations in the seismic waves could be attributed to physical changes at the inner core-outer core boundary.
By focusing on times when the core was in the same position and they could rule out the core's rotational shifts as the sole cause – they found evidence in support of these deformations, with sections potentially rising and falling by up to a kilometre over just a few years.
These findings challenge the traditional view of the inner core as a perfect sphere, but further research is required to fully understand these deep-Earth processes.
A long-lost relative
Paleontologists have identified a new species of Paranthropus, an extinct human relative, based on a 1.4 million-year-old jawbone found in South Africa in 1949. Previously misidentified as a species from the Homo genus (our genus), new advanced 3D scans revealed that the jawbone shares more characteristics with the Paranthropus genus – also referred to as the "nutcracker man" due to their defining massive jaws and huge molars. However, this discovery has a smaller than usual jaw and teeth, distinguishing it as a previously unknown species.
Named Paranthropus capensis, this species coexisted with early Homo species and likely had a more varied diet than Paranthropus robustus, a different Paranthropus species. This discovery suggests greater diversity within Paranthropus and may reshape our understanding of human evolution.
Lost even longer?
A team of scientists from Mexico, the US, and Spain has identified a new genus and species of ostrich-like dinosaur within the Ornithomimidae family. The fossil was discovered in Coahuila in 2014 but only recently had a fresh examination. The team were able to date the remains back approximately 73 million years. Distinguishable from others in its family due to its long hands – with a palm longer than its entire upper arm, similar to modern tree sloths, the species was promptly named Mexidracon longimanus.
