讲座内容简介:
The proximate, short-term, causes of outbreaks of locusts, including the Desert Locust Schistocerca gregaria, are combinations of the timings, geographical distributions and amounts of rainfall and associated vegetation growth. However, what controls these drivers, and the degree to which they are cyclic, is poorly understood. Various hypotheses, such as that sunspot activity plays a major role, have been advanced by entomologists since 1883 to account for long term patterns in locust numbers but statistical analyses have not offered strong evidence for any clear causal links. However, new mathematical techniques are able to demonstrate causality between time series. Results of applying such techniques to the analysis of the FAO data on numbers of territories infested with swarms of the desert locust from 1866 to 2015 will be presented after initial results based on spectral analysis.