Friday Headlines, March 6, 2020
THE LATEST IN THE GEOSCIENCES
This week in paleontology (AKA Fossil Friday)
- DNA from dinosaurs
This week in geology
- Pinpointing Indonesian earthquakes
This week in the environment
- Microplastics in deep-sea organisms
Cartilage cells, chromosomes and DNA preserved in 75 million-year-old baby duck-billed dinosaur
In the post Jurassic Park world, people wonder if dinosaur DNA will ever be found. Until recently, the scientific community said ‘no’ vehemently. Over the last decade more and more evidence for the preservation of soft material – blood vessels, collagen, etc – has been found. The authors of this paper found actual cartilage cells in the skulls of juvenile hadrosaurs called Hypacrosaurus. Not only were the cells preserved, but the chemical markers for DNA are also present.
Perhaps Jurassic Park isn’t so impossible after all?
Reference: Alida M Bailleul et al, Evidence of proteins, chromosomes and chemical markers of DNA in exceptionally preserved dinosaur cartilage, National Science Review (2019). DOI: 10.1093/nsr/nwz206 (Open Access)
Source of Indonesian earthquakes and tsunamis located
Indonesia is well known for its earthquakes and tsunamis. This is because the islands that comprise Indonesia are the result of a very complex set of small tectonic plates that are over and under each other in a process called subduction.
The massive 2011 earthquake and tsunami that struck Japan was also the result of subduction (as are the islands of Japan themselves).
Subduction occurs when two plates are moving toward each other (‘squishing’) and one must pass under the other. What the authors of this paper found was that in fact the Banda Sea Plate is stretching not squishing. Earthquakes are caused by faults formed near the surface due to this stretching and the tsunamis in this area are due to slumping of deep ocean sediments along these fault lines which may or may not be directly triggered by earthquakes.
The main conclusion: not all tsunamis are caused by subduction.
Reference: Phil R. Cummins et al. Earthquakes and tsunamis caused by low-angle normal faulting in the Banda Sea, Indonesia, Nature Geoscience (2020). DOI: 10.1038/s41561-020-0545-x (Pay-Wall)
The new face of the plastics crisis
The paper here is actually a description of a new species of amphipod (or “hopper”) that was discovered at great depth in the Mariana Trench between Japan and the Philippines.
The disturbing part of this discovery is that the amphipod had consumed a particle of polyethylene terephthalate (PET), a common plastic in households.
Because of the discovery of plastic in its tiny body, the researchers decided to name the amphipod Eurythenes plasticus to highlight the discovery of microplastic in its body.
Reference: Johanna N. J. Weston et al. New species of Eurythenes from hadal depths of the Mariana Trench, Pacific Ocean (Crustacea: Amphipoda), Zootaxa (2020). DOI: 10.11646/zootaxa.4748.1.9 (Open Access)
EPOCH isotopes 