Project properties
Title Population structure in ladybird beetles
Group Entomology, Laboratory of
Project type thesis
Credits 36
Supervisor(s) Dr P.W. de Jong
Examiner(s) Prof. M. Dicke
Contact info Peter.dejong@wur.nl
Begin date 2023/01/01
End date 2023/12/31
Description Organisms are adapted to their local environment. This may mean that there are geographic differences in the occurrence of alleles at adaptive loci. The frequency at a particular locality of a certain adaptive allele is not only influenced by selection, but also by processes that affect the whole genome, such as dispersal or migration. The role of the latter can be investigated with genome-wide sampling of variation at non-adaptive loci, such as microsatellites. If samples differ significantly in the frequency of alleles at such nonadaptive loci, this is an indication that genetic exchange between such samples is limited, in other words, that potentially there is an influence of a limitation of dispersal on the frequency of alleles at adaptive loci. One of the insect species receiving a lot of attention at present is the exotic ladybird beetle Harmonia axyridis. Surprisingly, population structure has hardly been investigated in this species, and it would in itself already be very interesting to study population structure in this beetle. What makes it even more exciting is the possibility to link such population structure with the occurrence of different color forms of this ladybird; there are predominantly red specimens with black spots, and black ones with red spots. These forms may occur at different localities with different frequencies. The color of the ladybirds is undoubtedly under selection, but the question is whether only selection is responsible for any differences in frequency of the color form alleles, or whether also a limitation of dispersal may play a role. This project requires sampling of ladybird populations in the field, scoring of color forms, and simple molecular analysis to study population structure. Since the beetles can be found in the field throughout the year, this project can start at any time.
Used skills PCR, sampling
Requirements For doing a BSc-thesis at Entomology, there are no requirements for specific courses.
For doing a MSc-thesis or internship at Entomology, the following requirements apply: ENT-30806 + a second ENT-course (preferably ENT-30306 or ENT-50806 or ENT-53806). As an alternative for the second ENT-course, PHP-30806 or BHE-30306 can be selected.
Note: these requirements do not apply for MBI students; MBI students should check the requirements for doing an ENT MSc-thesis or internship in the study programme of their specialisation.