Recent evidence from bluethroats (Luscinia s. svecica) suggests that optimal (intermediate) levels of MHC variability in offspring is achieved through extra-pair mate choice. One possible mechanism for obtaining a MHC-compatible mate is through odour signals. This depends on the existence of a link between MHC genes and the body odour of individual birds and this project will investigate whether odour-producing bacteria in the preen gland and/or on the feathers may constitute this link. Furthermore, the fitness consequences of having intermediate MHC variability will be investigated by screening for blood parasites and obtaining estimates of individual reproductive success. The main study species is the ground-nesting bluethroat, but similar questions will also be addressed in the blue tit (Cyanistes caeruleus). The latter is a nest-box breeding species, which removes the need for nest searching and facilitates obtaining better estimates of reproductive success.
There are several possible master projects connected to this research program:
Bluethroat
Project 1 (field and lab): MHC and the feather microbiome in bluethroats. The field work will consist of capturing adults in the fertile period (early June) and collecting feathers from different parts of the body, as well as preen gland oil. The student is also expected to participate in the field work for project 2. Lab work will involve analysing feather and preen oil microbiome, using 16S rRNA high-throughput amplicon sequencing. These data will allow testing for sex differences and similarities within pairs in microbiome diversity, as well as its relationship with MHC-variability.
Field work: ?vre Heimdalen field station, ?ystre Slidre, Innlandet, May-June 2021. Lab work: NHM DNA lab
Supervisors: Arild Johnsen and Erica Leder
Project 2 (field and lab): MHC, blood parasites and reproductive success in bluethroats. This project will be based on the same birds as in project 1 plus their offspring, and the student is expected to participate also in the field work for project 1. Additional field work consists of locating nests and collecting blood samples of adults and nestlings. In the lab, the student will screen for blood parasites with PCR-based method, allowing tests for relationships with MHC-variability.
Field work: ?vre Heimdalen field station, ?ystre Slidre, Innlandet, May-June 2021. Lab work: NHM DNA lab
Supervisors: Arild Johnsen and Jan T. Lifjeld
Project 3 (lab): MHC and mate choice in bluethroats. This is a lab-based project, but participation in field work will be possible if this is desirable. The other two bluethroat projects depend on data from this project, so if there are no students signing up for this project we will get the MHC-typing done through the use of technical assistance. The work will consist of genotyping of MHCII for samples already collected in 2017 and 2018, as well as new material from the 2021 field season. Genotyping will be done using high-throughput amplicon sequencing, followed by allele calling through bioinformatic analyses. This will allow testing for evidence of mate choice for intermediate MHC-variability (replicating an earlier study) as well as exploring relationships with preen gland chemical profiles.
Lab work: NHM DNA lab
Supervisors: Arild Johnsen and Silje Rekdal
Blue tit
Project 4 (field and lab): MHC and fitness in blue tits. A blue tit population at D?li, B?rum, has been studied since 1995 by Tore Slagsvold and co-workers. There are therefore plenty of blood samples and very good data on reproductive performance available for this population. There will also be a full field season in which additional data will be collected. The work will consist of nest box checking from the start of the breeding season, collecting blood samples of adults and nestlings, and collecting data on reproductive performance. Screening for blood parasites will be done with a PCR-based method. Tests for relationships between blood parasites, reproductive success and MHC variability will be performed.
Supervisors: Arild Johnsen and Tore Slagsvold,
Field work: D?li, B?rum, Viken, April-June 2021. Lab work: NHM DNA lab
Project 5 (lab): MHC and mate choice in blue tits. This is a mainly lab-based project, but participation in field work will be required, since it is highly beneficial with at least two students to perform this rather labour-intensive field work. Lab work will consist of genotyping of MHC using high-throughput amplicon sequencing, followed by allele calling through bioinformatic analyses. Project 4 depends on data from this project, so if there are no students signing up for this project we will get the MHC-typing done through the use of technical assistance. Blue tits are less promiscuous than bluethroats, and this project will therefore focus on social mate choice and test whether there is non-random mating with respect to MHC-compatibility.
Supervisors: Arild Johnsen, Silje Rekdal and Tore Slagsvold
Field work: D?li, B?rum, Viken, April-June 2021. Lab work: NHM DNA lab