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The anatomy of the Late Miocene baleen whale Cetotherium riabinini from Ukraine

100%

Gol'din P., Startsev D., Krakhmalnaya T.

Acta Palaeontologica Polonica

2014

tom 59

nr 4

We re-describe Cetotherium riabinini, a little-known baleen whale from the Late Miocene of the Eastern Paratethys represented by an exceptionally well-preserved skull and partial skeleton. C. riabinini is shown to be closely related to C. rathkii, the only other member of the genus. Cetotheriids from the Eastern Paratethys are remarkable for their pachyosteosclerotic postcranial skeleton, and are among the youngest known cetaceans displaying this morphology. C. riabinini likely followed a generalised feeding strategy combining herpetocetine-like continuous suction feeding, as seen in the mallard Anas platyrhynchos, and eschrichtiid-like intermittent suction feeding. This hypothesis may explain the mechanism and function of cranial kinesis in baleen whales. Many characteristics of the mysticete skull likely evolved as a result of cranial kinesis, thus leading to multiple instances of morphological convergence across different phylogenetic lineages.

Age-related changes in the teeth of two bat species: dental wear, pulp cavity and dentine growth layers

100%

Gol'din P., Godlevska L., Ghazali M.

Acta Chiropterologica

2018

tom 20

nr 2

As bats are long-lived mammals, insight into the age of individuals is important for studies relating to population ecology and conservation biology, as well as longevity. Thus, there is a need to develop methods to estimate the age of bats, and teeth are excellent means to do so. The work detailed here involves an assessment of age-related changes and variation in tooth wear, dentine growth layers, and pulp cavity size in two bat species with differing life history strategies, i.e. Nyctalus noctula (n = 149) and Eptesicus serotinus (n = 49). Both the gross morphology and the histology of teeth in both species were found to display age-related variation. Morphological indicators like tooth wear and pulp-cavity size showed considerable variation at the individual level, and corresponding with broadly defined age categories. Dentine growth layering was consistent with presumed age and had annual growth layers in both species, along with accessory layers. Aspects of interpreting growth layers and tooth wear based on photographs and histological preparations associated with observer bias are important to consider, as are the sampling of multiple readings.

Ograniczanie wyników

1 Acta Chiropterologica

1 Acta Palaeontologica Polonica

2 Gol'din P.

1 Ghazali M.

1 Godlevska L.

1 Krakhmalnaya T.

1 Startsev D.

1 2018

1 2014

Wyniki wyszukiwania

The anatomy of the Late Miocene baleen whale Cetotherium riabinini from Ukraine

Age-related changes in the teeth of two bat species: dental wear, pulp cavity and dentine growth layers