To build linkage maps for the Atlantic silverside and map key fitness traits to the genome, we had established several inter-population crosses between fish collected in Georgia and New York. The photo shows pure-bred F1 individuals raised under common conditions in the lab with parents from the two populations (top three fish have New York parents, the bottom three fish have parents from Georgia), illustrating the stark difference in growth rates. The inter-crossed F1 individuals have now matured, and our collaborator Hannes Baumann along with Maria and his team, successfully got them to spawn to form several large F2 families that we can use for mapping.
Maria has spent several weeks at the Baumann Lab at University of Connecticut Avery Point to measure traits in the F2 juveniles. She has been measuring length, weight, shape, routine metabolism, and maximum sustained swim speed of a total of 282 individuals. These data will be used together with genomic data for QTL mapping (to identify what parts of the genome affect the traits) as well as for generating a linkage map to examine the recombination landscape in the silverside. Here's a video showing a busy day in the Baumann Lab