Calcium Can Tell Us About Ancient Ecosystem Structure – #365papers – 2017 – 147

#365papers for May 27, 2017

Martin, Vincent, Tacail, Khaldoune, Jourani, Bardet, Balter, 2017, Calcium isotopic evidence for vulnerable marine ecosystem structure prior to the K/Pg extinction: Current Biology, v. 27

What’s it about?

The variations of the amounts of stable isotopes (that is non-radioactive) found in rocks and fossils can be used to help us understand patterns of weather, of vegetation, and of who’s eating whom in modern and fossil rocks, bones, teeth, and shells. Most of the time carbon, oxygen, and nitrogen are used for this.

The authors here show that calcium isotopes can be used to understand tropic level (where organisms are on the food chain) in modern and fossil animals. Their work shows that large marine reptiles likely went extinct at the end of the Permian Period because they all lived at the same trophic level. There was some sort of ecological change that eradicated their food supply and the marine reptiles could not recover. Continue reading

Extinction in the Permian – #365papers – 2017 – 146

#365papers for May 26, 2017

Lucas, 2017, Permian tetrapod extinction events: Earth-Science Reviews, v. 170, p. 31-60.

What’s it about?

The Permian ended with the largest marine extinction ever to strike the Earth, with 95% of species going extinct. This paper discusses life on land, specifically tetrapods (amphibians and reptiles at that time) and how they went extinct. Continue reading

Ann Hinga. Phone Call for Ann Hinga – #365papers – 2017 – 145

#365papers for May 25, 2017

Stidham, Patnaik, Krishan, ingh, Ghosh, Singla, and Kotla, 2017, The first darter (Aves: Anhingidae) fossils from India (late Pliocene): PlosONE, v12, e0177129

What’s it about?

There’s a family of birds called the Anhingidae, which includes anhingas and darters. This is a description of a new fossil darter from India. Continue reading

When Did We Stop Being Apes? – #365papers – 2017 – 143

#365papers for May 23, 2017

Fuss, Spassov, Begun, and Bohme, 2017, Potential hominin affinities of Graecopithecus from the Late Miocene of Europe: PlosONE, v. 12, e01771127

What’s it about?

Yesterday’s paper was about the age of the new species Graecopithecus, an early relative of humans. This paper discusses what separates Graecopithecus from other apes and what unites it more closely with humans.

Why does it matter?

With a clear definition of what distinguishes humans and their closest relatives from apes, and by also having an age for the oldest member of the human lineage, we can better understand how we came to be who we are.

Why did I read this?

This paper was all over social media. I felt obligated to read it.

Maybe the oldest hominin? – #365papers – 2017 – 142

#365papers for May 22, 2017

Bohme, Spassov, Ebner, Geraads, Hristova, Kirscher, Kotter, Linnemann, Prieto, Roussiakis, Theodorou, Uhlig, and Winklhofer,  2017, Messinian age and savannah environment of the possible hominin Graecopithecus from Europe: PlosONE, v. 12, e0177347.

What’s it about?

Hominins are humans and their non-ape ancestors. Graecopithecus appears to fall into this group. Using geochemical methods plus study of the sediments that the fossils came from, the researchers show that this fossil is the earliest hominin by a few hundred thousand years and that the environment was one of wooded grasslands or braided streams and supports the ‘Savannah Hypothesis’ of human evolution. Continue reading

Because Isotopes of Carbon and Oxygen Are So Last Century… – #365papers – 2017 – 141

#365papers for May 21, 2017

Martin, Tacail, and Balter, 2017, Non-traditional isotope perspective in vertebrate palaeobiology: Palaeontology, p. 1-18.

What’s it about?

The authors discuss the utility of isotopes of calcium, magnesium, copper, iron, and zinc for study of ancient environments, dietary preferences, and food chains. Continue reading

Animal Extinctions Don’t Mean Plant Extinctions – #365papers – 2017 – 140

#365papers for May 20, 2017

Barbacka, Pacyna, Kocsis, Jarzynka, Ziaja, and Bodor, 2017, Changes in terrestrial floras at the Triassic-Jurassic Boundary in Europe: Palaeogeography, Palaeoclimatology, Palaeoecology, v. 480, p. 80-93. http://dx.doi.org/10.1016/j.palaeo.2017.05.024.

What’s it about?

A major mass extinction terrestrial and marine animals occurred at the Triassic-Jurassic boundary. Here, the authors examine whether land plants also suffered an extinction. It appears that plants were largely unaffected. Continue reading

Volcanoes and the Late Ordovician Extinction – #365papers – 2017 – 139

#365papers for May 19, 2017

Jones, Martini, Fike, and Kaiho, 2017, A volcanic trigger for the Late Ordovician mass extinction? Mercury data from south China and Laurentia: Geology,

What’s it about?

One of the “Big Five” mass extinctions that has affected life on this planet is the Late Ordovician mass extinction or LOME. The causes of such extinctions are topics of focused research efforts. Here, the authors show that pulses of volcanic activity may be related to the extinction events. Continue reading

All Your Carcass Are Belong in Carnivore Belly – #365papers – 2017 – 138

#365papers for May 18, 2017

Chichkoyan, Figueirido, Belinchon, Lanata, Moigne, Martinez-Navarro, 2017, Direct evidence of megamammal-carnivore interaction decoded from bone marks in historical fossil collections from the Pampean region: PeerJ 5:e3117; DOI 10.7717/peerj.3117

What’s it about?

Trace fossils (scratches, pits, fractures) on the fossils large mammalian herbivores from the Pampean region of Argentina are used to infer that carnivores completely utilized the carcasses of their prey. Continue reading

Dinosaur Fossils: Dating the Rock to Date the Bones – #365papers – 2017 – 137

#365papers for May 17, 2017

An, Kuang, Liu, Peng, Xu, Xu, Zhang, Wang, Chen, and Zhang, 2016, Detrital zircon dating and tracing the provenance of dinosaur bone beds from the Late Cretaceous Wangshi Group in Zhucheng, Shandong, East China: Journal of Palaeogeography, v. 5, 72-99.

What’s it about?

Geochemical and sedimentological methods are used to determine the age and provenance (i.e. where did the sediments come from) of dinosaur-bearing rocks. The bones themselves could not be directly dated, but cannot be younger than the rocks they’re found in. Continue reading