Current project(s): Multiple projects including some on the complexity and stability of large biological systems, biosecurity and risk sharing.
Advice to aspiring scientists:“Read fiction. Honestly. Reading books keeps your brain open. Shifts in focus, twisted perspectives, surprise connections… it’s what research should be.”
Selected publication: Doehl, J.S.P. et al., 2017. Skin parasite landscape determines host infectiousness in visceral leishmaniasis. Nature communications
Whether or not we are happy to accept it, natural variation through chance plays a significant role in our own lives. It has made each of us unique through random genetic mutation, but it is also central to explaining many other natural phenomena. Variation by chance is often adjusted for under lab conditions through the repetition of trials. In reality, nature is highly dynamic and we are nowhere near completely understanding all of its intricacies, many of which rely heavily on chance. Considering the influence of chance alongside other factors allows for an increased understanding of nature and leads scientists towards the path of applying gained knowledge to solve real-world problems.
Understanding how natural randomness interacts with other factors to influence nature has been the work of Dr Jon Pitchford, a mathematical ecologist who has come to accept that there isn’t always a simple deterministic pattern to be found. This realisation allows him to improve current statistical methods not accounting for natural variability with his colleagues. They also create mathematical models which aim to make sense of certain natural phenomena influenced by natural variability such as animal movement and disease transmission.
A great example which demonstrates that natural variability needs to be considered when working with living organisms is seen in Dr Pitchford’s work, with York colleagues in Biology and Mathematics on circadian rhythms: the biological clocks which cause daily changes within living organisms (such as our tendency to sleep at night). They studied how the circadian rhythm of a certain plant species changes under different concentrations of lithium; measuring the changes in the expression of certain genes over time as a proxy for circadian rhythm. The most commonly used methods of statistical analysis for such data assumes that the statistical properties of the data set, such as variance, remain constant over time. This constancy of statistical properties known as stationarity doesn’t really occur unless the specimen is dead. This means that any analytical method which doesn’t account for changes in statistical properties over time can produce unreliable results. What Dr Pitchford and his colleagues have deduced is that living systems do show stationarity over very short periods of time and that the data can be bundled into distinct packages called wavelets. Each wavelet can be analysed as a piece of a larger data set in order to allow the changing statistical properties of the data set to be accounted for. In other words, they have devised a way to adjust for the randomness of life through the development of a new statistical method allowing for the generation of more accurate scientific data.
Alongside his involvement in research here at the UoY, Dr Pitchford works with the Science advisory committee for the UK’s Centre for Environment, Fisheries and Aquaculture Science (CEFAS) as an impartial mathematician. The climbing and beer enthusiast recognises the beauty of maths and has been able to help conduct research into human disease, biosecurity, toxicology, algal blooms and more. Despite not being particularly knowledgeable in each of these subjects, his broad knowledge of mathematics has provided him with the opportunity to work across a range of specialities. He recognises that mathematics will continue to play a major role in biological research in the coming years, especially in our current age of data abundance and affordable computation. Dr Pitchford’s work is a testimony to the fact that science isn’t always as clear-cut as it’s made out to be and that variability is as, if not more, important as the means of any data set. On his research page, Dr Pitchford has written “Getting lucky can be better than being good” a statement which communicates how truly unpredictable nature can be.