University of Otago palaeontologists are rewriting the history of New Zealand's ancient whales by describing a previously unknown genus of fossil baleen whales and two species within it.
Otago Department of Geology PhD student Robert Boessenecker and his supervisor Professor Ewan Fordyce have named the new genus Tohoraata, which translates as 'Dawn Whale' in Māori.
University of Otago researchers have described a new genus of ancient baleen whales that they have named Tohoraata (a Māori term which can be translated as Dawn Whale). The genus belongs to the toothless filter-feeding family Eomysticetidae, and it is the first time members of this family have been identified in the Southern Hemisphere. They named the younger of the two fossil whales, which may be a descendent of the elder, as Tohoraata raekohao (pictured). Raekohao means 'holes in the forehead'. Researcher Robert Boessenecker says this whale lived between 26-25 million years ago and vaguely resembles a minke whale but was more slender and serpent-like. Its skull, which contains a number of holes near its eye sockets for arteries, was probably about two metres in length and the whole animal would have been eight metres long.
Credit: Robert Boessenecker
The two whales, which lived between 27-25 million years ago, were preserved in a rock formation near Duntroon in North Otago. At that time the continent of Zealandia was largely or completely under water and the whales were deposited on a continental shelf that was perhaps between 50 to 100 metres deep.
The new genus that the fossils represent belongs to the toothless filter-feeding family Eomysticetidae, and it is the first time members of this family have been identified in the Southern Hemisphere.
They named the younger of the two fossil whales, which may be a descendent of the elder, as Tohoraata raekohao. Raekohao means 'holes in the forehead'.
Mr Boessenecker says this whale lived between 26-25 million years ago and vaguely resembles a minke whale but was more slender and serpent-like. Its skull, which contains a number of holes near its eye sockets for arteries, was probably about two metres in length and the whole animal would have been eight metres long.
"This new species differs from modern baleen whales in having a smaller braincase and a skull that is generally much more primitive, with substantially larger attachments for jaw muscles. The lower jaw retains a very large cavity indicating that its hearing capabilities were similar to archaic whales."
The researchers also determined that the older fossil whale from the site, which was collected in 1949 and named in 1956, had been misidentified as belonging to the genus Mauicetus, a more advanced type of whale called a "cetothere". They have now changed its name from Mauicetus waitakiensis to Tohoraata waitakiensis.
Mr Boessenecker says this particular fossil had been poorly understood for more than 50 years and only with this study was it proven not to be from its originally attributed genus. The two whales have now become the first eomysticetids to be reported outside of South Carolina, USA, and Japan.
"Researchers contend with confusing or surprising fossils in museum collections all the time. Often, the best way to solve these mysteries is to go out and dig up another one, which is what Professor Fordyce and his colleagues did in 1993 when they collected the partial skull of Tohoraata raekohao."
Eomysticetids occupy an important position in the evolutionary tree of cetaceans: they are the earliest toothless baleen-bearing cetaceans, and in many characteristics are intermediate between toothed baleen whales and modern baleen whales, he says.
"They are the first baleen whales to have been completely toothless, and are therefore the earliest known cetaceans to have wholly relied upon filter feeding."
This study formed part of Mr Boessenecker's PhD thesis and was supported by a University of Otago Doctoral Scholarship. The Tohoraata raekohao fossil was collected during fieldwork funded by a grant from the National Geographic Society.
Robert Boessenecker | EurekAlert!
In times of climate change: What a lake’s colour can tell about its condition
21.09.2017 | Leibniz-Institut für Gewässerökologie und Binnenfischerei (IGB)
Did marine sponges trigger the ‘Cambrian explosion’ through ‘ecosystem engineering’?
21.09.2017 | Helmholtz-Zentrum Potsdam - Deutsches GeoForschungsZentrum GFZ
Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.
The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...
Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...
Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!
When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...
For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.
Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...
MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems Holding GmbH about commercial use of a multi-well tissue plate for automated and reliable tissue engineering & drug testing.
MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems...
19.09.2017 | Event News
12.09.2017 | Event News
06.09.2017 | Event News
21.09.2017 | Physics and Astronomy
21.09.2017 | Life Sciences
21.09.2017 | Health and Medicine