Our research on African mammals takes two directions. The first is the study of various aspects of the biology of underground rodents, the second is mainly taxonomic studies on a number of small mammals.

 

Underground rodents are mammals that have "chosen" a demanding form of existence, as they live all their lives under the Earth's surface. Compared to the conditions above ground, such a way of life offers a number of advantages – especially a greater degree of safety from predators and also the microclimatic stability of the environment (no wind, higher temperature, constant humidity). But, as always, the advantages are balanced by a number of disadvantages – it is dark in the burrows, there is little oxygen and high levels of CO2, and it is necessary to burrow through the soil for food. Due to this hidden way of life, until recently we knew little about the biology of underground rodents. African mole rats are one of the most famous underground dwellers. Our research focuses on little-known both solitary and social species from Central and East Africa (Malawi, Zambia, Tanzania). Recently, we have begun to study other underground rodents such as the big-headed African mole-rat in Ethiopia and the Middle East blind mole-rat in Israel. In the future, we plan to focus on other representatives, such as zokors in China.

 

The goals of our research are to find out how these animals cope with the drawbacks of a very demanding way of life underground. In our research, we strive to consistently link field and laboratory approaches. In nature, we focus on the ecology and behavior of underground mammals in burrow complexes. We use radio transmitters to monitor their activity and evaluate the factors that affect it. We also deal with the role of these perfect "tunnelers" in local ecosystems and use genetic methods to analyze their reproductive systems. Experiments in breeding at the Faculty of Science (where we have built the most representative collection of underground mammals in the world) are used to verify and supplement knowledge from the wild. As for our research in the laboratory, we are mainly interested in sensory ecology (magnetic orientation, and optical and olfactory abilities) and communication. Part of our research is also ecophysiological studies focusing on adaptations that allow mammals to survive underground, or on how beneficial socialism is from a thermoregulatory point of view.

 

The development of molecular genetic methods have helped us to reveal the influence of various factors on the composition of fauna of specific geographical areas. Some parts of our planet, such as large areas of Africa, are still very little studied in this regard. In the second round of our research on African mammals, in collaboration with Josef Bryja from the Institute of Vertebrate Biology in Brno, we are focusing on this type of research, especially in Eastern and Central Africa. These parts of the continent are very suitable for this type of study. Geological activity has created a very diverse landscape with striking mountain massifs, isolated volcanoes, but also vast lowlands. The most striking local geological formation is the Great Rift Valley, which, together with large rivers, which often change their courses, is a significant barrier to overcome for small mammals that move low to the ground. In addition, the last few million years in Africa have seen regularly alternating dry periods, when savannas, semi-deserts, or deserts have expanded, and wetter periods, during which, in contrast, more humid vegetation, such as rainforest, has expanded. Physical barriers, together with the repeated enlargement and shrinking of suitable environments, have contributed to the isolation of individual populations, which has resulted in a striking genetic structure and sometimes the emergence of new species. It is no wonder that this part of Africa is one of the places with the greatest diversity of mammals.

  

During field expeditions, we strive to capture rodents, insectivores and, in some cases, bats in as many localities as possible across large areas to capture the genetic variability of individual groups. We supplement our collections (so far Mozambique, Malawi, Zambia, Tanzania, Kenya and Ethiopia) with samples from colleagues from foreign institutions or with DNA sequences from available databases. Thanks to detailed imaging, we are able to use various methods to determine the relationship of individual populations and species and estimate when they separated from each other. Knowledge of historical geological and climatic processes, which were accompanied by changes in vegetation, allows us to identify the factors that determine the genetic diversity of the studied groups, the composition of small mammal communities and the geographical distribution of individual species. Morphological analysis of the collected material is also part of our work. In addition to the description of the genetic diversity of individual groups, we focus on the taxonomic interpretations of our results and the description of new species.

This research takes place at the Department of Zoology, contact person doc. Radim Sumbera (sumbera@prf.jcu.cz).