Tina Del Carpio
Department of Ecology and Evolutionary Biology, UCLA, Lohmueller Lab
“The Evolutionary Patterns of Recombination Rates in North American Gray Wolves (Canis lupus) and Domestic Dog”
Authors: Christina (Tina) A. Del Carpio*, Maria Izabel A. Cavassim*, Pedro Perez, Robert K. Wayne, Kirk E. Lohmueller
Meiotic recombination is a notable mechanism that, in sexually reproducing species, permits the proper alignment and segregation of homologous chromosomes while also generating novel combinations of alleles in populations. Recombination rates are known to vary on the level of species, populations, sexes, and individuals. Thus, it is a trait that can be acted upon by forces of evolution such as natural selection and drift. Here we investigated the possible changes in recombination rate due to the process of domestication in canids. We estimated rates of recombination and locations of recombination hotspots (rates ≥5X background rates) from high-coverage WGS data from a population of North American (NA) gray wolves and over ten breeds of domestic dogs. We used the software pyrho which incorporates population patterns of linkage-disequilibrium (LD) and demographic history. Preliminary results for wolves (n = 14, mean coverage = ~38X) and the dog breed of pugs (n = 15, mean coverage = ~48X) show that wolves have a higher mean recombination rate. Simulations suggest that this difference in mean recombination rate is not driven solely by differences in demography. Future analysis includes identification of recombination hotspots and comparisons of their locations between populations as well as inclusion of more breed dogs and the rest of the canid genome. This work will result in fine-scale recombination maps for NA gray wolves and several domesticated dog breeds. Comparisons of these maps will highlight the possible changes in recombination rate between these sister taxa since dog domestication. Better understanding how recombination rates can change scale and/or location in closely related species can inform how this trait changed through time.
Department of Ecology and Evolutionary Biology, UCLA, Shaffer and Wayne Labs
“An Iterative Modeling Approach to Adaptive Management of Invasiv Crayfish in Southern California Streams”
In Southern California, the invasive red swamp crayfish (Procambarus clarkii) poses a significant threat to native aquatic fauna. Local conservation managers have led eradication efforts since 2010, but little empirical research has been done to improve the efficacy of this work. In this presentation, I will explore two empirical studies that I lead to improve crayfish removal efforts locally. In the first study, De-Palma Dow et. al (2020), we used zero-inflated Poisson regression model and post-hoc mean comparison test to explore the differences in mean trap catch of invasive crayfish and two native aquatic taxa. Ultimately, conservation managers can use the findings from this paper in order to choose the most efficacious crayfish trap for their stream system given the species assemblage therein. Next, I will discuss the second empirical study, Curti et al. (2021), where we develop a novel crayfish trap that mimics crayfish burrows and employ a similar modeling approach to demonstrate that this trap is a valuable tool in removing crayfish that results in no native bycatch. Finally, I will discuss how partnerships with local conservation agencies and scientists can lead to important and productive long-term collaborations.