Under this Research Fellow project funded by the Research Council of Finland we explore various topics related to the overarching topic of reconstructing climatic and environmental conditions, and properties of biomes or plant communities, in the distant past when the functional trait distributions in terrestrial mammal communities were drastically different from present-day communities. We seek to find alternative ecometrics (functional traits in fossil mammal communities, including tooth morphology and wear, body size and limb bone proportions) to apply for reconstructions of climate and plant communities in more distant times than the last ca. 15-10 million years when trait distributions more or less equal to present mammal communities had evolved. Various topics within this overarching research project include Cenozoic mammal ecometrics of South America (PhD project of Oscar Wilson), dental ecometrics and diet on non-analogue mammal communities in Europe and East Africa during the Cenozoic (Juha Saarinen) and postcranial ecometrics of large herbivorous mammals (Steven Zhang).
Researchers: Juha Saarinen, Oscar Wilson, Steven Zhang
As the largest terrestrial herbivorous mammals in most parts of the world during the last ca. 25 million years, elephants and their fossil relatives (Proboscidea) have had a profound ecological impact in terrestrial environments for most of the recent history of the Earth. On the other hand, as very large and ecologically versatile animals with non-selective feeding habits, their diet and adaptations reflect local changes in climate and vegetation during the Cenozoic perhaps better than those of any other group of terrestrial mammals. Various aspects of proboscidean evolution, paleoecology and response to climate and vegetation in past environments have been studied in the Evolutionary Paleontology Research Group, including large-scale studies of diet and dental evolution, and more recently, body size and limb proportions.
Researchers: Juha Saarinen, Steven Zhang, Pauline Mbatha
Dental mesowear analyses are based on the worn shape of the molar teeth of large herbivorous mammals, which gives a robust signal of lifetime average dietary composition of diet, especially the proportions of grass and browse in diet. When analyzed across large herbivore communities, or for dietary non-selective megaherbivores such as proboscideans, mesowear can also provide a signal of local plant community properties in the past. We develop mesowear analyses into more universally applicable and quantitative form by mesowear angle analysis, where the amount of abrasion on worn tooth surfaces caused by eating grass is measured as angle measurements from dentine valleys and enamel facets on the teeth. This broadens the application of mesowear analysis on all groups of large mammals, thus opening new possibilities for comprehensive community-wide dietary analyses.
Researchers: Juha Saarinen, Oscar Wilson
Body size is an essential trait of all organisms and it is connected with several of their physiological and ecological characteristics. Thus, there are important connections between climate, vegetation and body size variation in mammal species, as well as body size distribution in mammal communities. In our research group we have explored the effects of environment and diet on body size of mammals during the Cenozoic, including modelling of environmental conditions based on body size distributions.
Researchers: Juha Saarinen, Oscar Wilson
While postcranial ecomorphology of some groups of large mammals, such as bovids and horses, is relatively well understood, it remains more elusive in other ecologically important mammal groups. In our research group, we explore the interconnections between limb bone proportions of megaherbivorous mammals, especially proboscideans (PhD project of Pauline Mbatha) and rhinoceroses (Steven Zhang), and their environments in present and past terrestrial ecosystems.
Researchers: Pauline Mbete Mbatha, Steven Zhang