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#1: Mass extinction survival heros

While an asteroid wiped out most living beings on the planet 66 million years ago, including the dinosaurs, some species managed to survive, among which some ammonites. At least for quite a while.

Until recently, it was believed that ammonites (relatives of octopusses and squids) had also fallen victim to the asteroid impact, which caused an extreme tsunami and volcanic activity, covering the skies with ashes and acidyfying the oceans, fatal for shelled animals such as ammonites. However, recent studies of sediments near Copenhagen, where ammonite shells of three different genera were found, have led researchers to conclude that these animals continued to live until 68,000 years after the mass extinction event. The reseachers believe that these ammonites had been protected by an isolated environment, but later became extinct due to falling sea levels and declining genetic diversity.

https://www.science.org/content/article/against-all-odds-curious-sea-creature-survived-dino-killing-asteroid

#2: Virus für Walsterben verantwortlich?

Die häufigen Strandungen von Walen könnten auf ein Virus zurückzuführen sein, das Nerven, Immunsystem und Atemwege von Meeressäugern schädigt.

Dass das Cetacean Morbillivirus eine Rolle dabei spielt und dass es hochansteckend für Wale und Delfine ist und auch via andere Spezies übertragen werden kann, war bereits bekannt. Doch bisher gelang es nicht, lebende infizierte Tiere zu identifizieren. Forscher haben eine Methode entwickelt, wie dank Drohnen die von Walen ausgeatmete Luft analysiert werden kann. Sie hoffen, dadurch bestehende Bedrohungen rascher erkennen und Schutzmassnahmen bestimmen zu können.

https://www.derstandard.de/story/3000000301990/toedliches-virus-im-atem-von-walen-aufgespuert

#3: Bigger fish shoals, better decisions

This sounds like a story from the field of big data computing. A study shows that large fish shoals decide faster and more appropriately to a predator bird attack by diving down all at once, with low probability of misbehaviour.

The study was conducted on free-living Sulphur mollies (Poecilia sulphuraria), a species dwelling in large shoals at the surface and is therefore frequently attacked by birds. The mollies do not dive just once to escape, but repeat this behaviour to discourage the birds. The mollies react in the same way to other disturbances, but only once when they realise that they are harmless. 

It is unclear whether this finding can be generalised for other fish species that form large shools or shoals is unclear. Above all, however, with all the experience at hand, it seems unlikely that this can be observed in human crowd, not least because we have not lived freely for many generations. Swarm intelligence, anybody?

https://www.science.org/doi/10.1126/sciadv.adt8600

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