2017 Irving-Scholander Memorial Lecture
|Name:||Professor Barry Lovegrove|
|School of Life Sciences. University of KwaZulu-Natal, South Africa.|
|Date:||Thursday, 31 August 2017|
|Time:||6:00PM - 7:00PM|
|Location:||Murie Life Science Bldg, Murie Auditorium.|
Recent palaeontological data and novel physiological hypotheses now allow a time-scaled reconstruction of the evolution of endothermy in birds and mammals. A three-phase iterative model describing how endothermy evolved from Permian ectothermic ancestors is presented. Phase One proposes that the elevation of endothermy – increased metabolism and body temperature (Tb) – complemented large-body-size homeothermy during the Permian and Triassic in response to the fitness benefits of enhanced embryo development (parental care) and the activity demands of conquering dry land. Phase Two commenced in the Late Triassic and Jurassic and was marked by extreme body-size miniaturization, the evolution of enhanced body insulation (fur and feathers), increased brain size, thermoregulatory control, and increased ecomorphological diversity. Phase Three occurred during the Cretaceous and Cenozoic and involved endothermic pulses associated with the evolution of muscle-powered flapping flight in birds, terrestrial cursoriality in mammals, and climate adaptation in response to Late Cenozoic cooling in both birds and mammals. Although the triphasic model argues for an iterative evolution of endothermy in pulses throughout the Mesozoic and Cenozoic, it is also argued that endothermy was potentially abandoned at any time that a bird or mammal did not rely upon its thermal benefits for parental care or breeding success. The abandonment would have taken the form of either hibernation or daily torpor as observed in extant endotherms. Thus torpor and hibernation are argued to be as ancient as the origins of endothermy itself, a plesiomorphic characteristic observed today in many small birds and mammals.
About the Speaker:
Barry Lovegrove was born in Salisbury, Southern Rhodesia, now Harare, Zimbabwe, in December 1956. He is the second eldest of six brothers. His family emigrated to his father’s home country, South Africa, when Barry was 6 years old. The family settled in Cape Town where Barry attended the South African College School (SACS) primary and secondary schools in Newlands. He studied zoology at the University of Cape Town and obtained his PhD specialising in animal energetics under the supervision of Gideon Louw in 1987. The title of Barry’s thesis was “The energeics of sociality of the molerats (Bathyergidae)”.
After a short spell of teaching at UCT, Barry undertook a post-doctorate program in the laboratory of Ken Nagy at the University of California, Los Angeles in 1988. There he also interacted with the reknowned American animal physiologist Bart Batholomew – he caught bumblebees in Bart’s magnificent garden – and the innovator of the popular Sable Systems respirometry equipment, John Lighton, with whom Barry also worked in Gideon Louw’s laboratory at UCT. In 1989 Barry undertook a post-doctoral program as an Alexander von Humboldt Fellow in the laboratory of Gerhard Heldmaier, Marburg, Germany. Heldmaier is perhaps the world’s foremost expert on the phyisology of non-shivering thermogenesis. Barry’s intention thereafter was to undertake research on melatonin and the function of the pineal gland in blind molerats with Russel Reiter, in Texas. However, then the Berlin wall came down which announced the death knell of the cold war, the global threat of communism, and the demise of apartheid in South Africa. Barry was lured back to South Africa by Gideon Louw, then the Director of the Foundation for Research Development, to help buffer the disastrous brain drain that South Africa had experienced during the 1980s.
Barry’s return to southern Africa did not go according to plan. The FRD was preparing for a new government and panicked; they cancelled all national and international post-doctoral programs overnight while they tried to figure out how to make their funding system more representative of a non-racialised society. With nothing to do and no job in sight, Barry spent nine months writing the Living Deserts of Southern Africa in Cape Town. In 1992 Barry secured his first and only permanent academic position at the former University of Natal, now the University of KwaZulu-Natal. He retired aged 60 in 2016, but retains Emeritus Professor status.
Barry has been interested in small bird and mammal energetics throughout his carreer. However, his research during the last decade, especially that in Madagascar on tenrecs, allowed him coalesce his work under a single umbrella topic, namely the evolution of endothermy in birds and mammals. He has written a book on his ideas titled Fires of Life: the evolution of endothermy in birds and mammals, which will be published by Yale University Press later this year.