Museum collections are an extremely valuable resource for recording the history of populations of bee species. Physical insect specimens are essential for 1) morphological identification of species, 2) recording when adults are active during the season, 3) where the bees were found, and 4) what flowers they were visiting. All of this provides rich historical data of bee populations over time. However, some data can be sparse, sometimes inaccurate, or incomplete because identifying bees is difficult and often different species look very similar to each other. Furthermore, collecting only a few specimens each year does not provide an estimate of the size of the population at that time.
Research using genetic information has dug deeper into the history and evolution of insect species. Often species show signs of genetic change or differentiation that cause speciation well before the show obvious changes in morphology. What if we could access this information from rare or extinct bee species, now only found in museums, to get a better understanding of the structure of the tree of life?
Also, we are concerned for the status and health of bee populations all over the globe. But because studies of bee population sizes and bee disease have only begun recently, we have very little to compare to from the past to find evidence of change. Genetic studies can actually determine measurements of population size from small numbers of samples when comparing populations in the same region. Also, using genetic information is the most accurate way of detecting diseases and pathogens. Therefore, museum bee collections may be the only way to estimate bee population sizes and disease prevalence in the past.
We are currently conducting a study to determine what genetic information can be accessed from museum curated bees, while causing little to no damage to the specimens (Fig. 1). Our study includes developing detailed and specific methods for how to extract and purify DNA from museum bees, and what the overall quality of this DNA would be (because it does degrade over time). We are then testing this DNA to determine if we can use genes for resolving taxonomic differences and detecting diseases. Finally, we are using the most current next-gen sequencing techniques to find out if we can determine population size and structure from the past. These methods we are developing are the first step in opening a new door to a wealth of information about the history of our planet.
Written by Anthony Vaudo, Postdoc in the López-Uribe Lab