Science Drinks – Feb. 25, 2014
Science Drinks kicked off with Gregor explaining exciting progress he has made in his honours project work. Gregor is using mapping techniques (GIS) to examine the phenology of dance flies across the UK, trying to find whether there is a difference in emergence times across dance fly species which display both conventional and reversed sex roles.
Luc then presented to the group a paper recently accepted in Evolution looking at age-dependent performance and senescence in sport (Lailvaux, Wilson & Kasumovic 2014). The authors used an extensive dataset on male and female professional basketball players to investigate sex differences in ageing and performance. The main results included a trend for earlier senescence in males, and evidence that different male performance traits showed varying rates of senescence. The Science Drinks group discussed the paper at length, especially how aspects of the data and game were controlled for in the analyses.
Whilst the paper made me realise how very little I know about basketball it prompted a long discussion about the use of sport stats (of which there are apparently huge repositories for some sports) in scientific analyses. Luc explained his ongoing interest in analysing sumo wrestling statistics and then went on to describe a paper he co-authored in 2004. This paper used data from cricket (the sport not the insect) to show that there was evidence of negative-frequency dependent success of left-handed batsman in the 2003 cricket World Cup. After the group chatted about cricket for a while I added both cricket and sumo wrestling to the quickly growing list of sports I know absolutely nothing about! The discussion then moved on to the group pondering what other sports may have large and detailed datasets, collected and published by enthusiasts, that could be used to answer biological questions.
Adam was next to speak and gave us a very interesting introduction to his work. His main interests are senescence and menopause in mammals and he currently uses a large dataset of human birth and death records to answer questions in this field. This dataset was collected from pre-industrial Finnish church records that are apparently extensive and very detailed. He is currently using the dataset to try and find the effect that number of children has on maternal fitness and survival. An issue that he has found in this system is that if a mother died, her offspring often died soon after, meaning the causal relationship is reversed (a lack of maternal care affects child survival, rather than the birth of children affecting mothers). The challenge of disentangling complex causal relationships appears to be a persistent problem for life history research.
Finally, Stuart talked us through some thoughts he was having in his own field of study using Daphnia to look at host-parasite coevolution. A major interest of his currently surrounds the idea that not every parasite will successfully infect a host and will instead simply pass through the host’s digestive system unharmed. He is looking into the cost of a failed infection on the parasite and how this affects both host and parasite population dynamics and coevolution.