As a new beekeeper, I never really considered much about the origins of honey bees. I knew they were not native to the United States, most are from Europe and the ones that sting in a swarm are called Africanized. Local beekeepers talk about ordering Italians or Carniolans to populate hives, and during a recent local beekeeper’s association presentation, Asian honey bees were mentioned. From where Apis mellifera, the Western honey bee arose, I did not know.
As it turns out, the origin of honey bees is a highly debated topic. Some say they arose from Asia; others say Africa. Recently, researchers from the University of California—Davis used short nucleotide polymorphisms (SNPs) and two sets of previously published whole genome data, included additional sequenced genomes and applied multiple computational methods to analyze honey bee population genetics. They published their conclusions in Genome Biology and Evolution. Continue reading “From Whence You Came, Honey Bee?”
The ability for adults to digest the milk sugar, lactose, is often referred to as lactase persistence (LP), describing the continued (persistent) production of lactase into adulthood. LP is an autosomal dominant trait that is most often associated with a T allele situated 13,910 base pairs (–13,910*T allele) upstream of the lactase gene, LCT. Archaeogenetic data indicates that pre- and early Neolithic populations were largely LP-negative, and that the frequency of the LP phenotype rose dramatically in Europe around 8,000 years ago, coinciding with the Neolithic transition from a hunter-gather to an agricultural-based lifestyle (1) and the appearance of domesticated dairying animals. Today roughly 35% of adults are lactose persistent. The frequency varies dramatically by geographic region, from a high prevalence in Europe (89–90%) and to a relatively low prevalence in the eastern Mediterranean (15%)(1). The spread of lactase persistence is an often cited example of gene-culture co-evolution. You can’t separate the history of domestic dairying and the evolution of lactase persistence, but scientists are still trying to understand how these two worked together. Continue reading “What Came First: LP or the Cow? Genetic and Cultural Co-evolution of Lactase Persistence and Dairying”
If you are of a certain age, the name “Tasmanian Devil” most likely conjures up an image of a ferocious brown hairy cartoon character that traveled in the center of a tornado of chaos. Sometimes, as in this case, the truth is much less strange than the fiction. The real Tasmanian Devils (Sarcphilus harrisii) are relatively small, somewhat cuddly looking, marsupials found only on the island of… you guessed it, Tasmania. Despite their diminutive size, they are the largest living carnivorous marsupial. Unfortunately, these terrier-sized animals are also in danger of becoming extinct, largely as a result of a deadly, infectious transmissible cancer called Devil Facial Tumor Disease (DFTD). Continue reading “The Devil is in the Details: Genetic Diversity and the Endangered Tasmanian Devil”
The genetics of wild cheetah (Acinonyx jubatus) populations has a special significance for me. In fact, it could be said that the population genetics of cheetahs changed my life. I first learned about the low genetic variability in cheetahs in a darkened lecture hall at Iowa State University in 1988. I was so fascinated by what I learned in those lectures about genetics and its importance in conservation efforts that I eventually changed my major to Genetics. “The Cheetah Papers” as a colleague calls them, were, and perhaps still are, common teaching tools for biology and genetics classes. And why not? The results were amazingly cool, if a bit disturbing. Imagine a population that, through a series of natural events over thousands of years, had become so genetically similar to one another as to be almost clonal.
It is sad but true that the latest news has not been promising for wild tiger populations. In September, an article published in PLoS Biology (1) estimated that the best hope of saving the wild tiger population would be to shift focus to source sites, which are “…at spatially well-defined priority sites, supported by proven best practices of law enforcement, wildlife management, and scientific monitoring.” The authors estimate the cost to save these sites at $82 million (U.S). At the time of publication, $47 million had been committed by governments and other groups. It isn’t difficult math to figure out there is a deficit. Continue reading “The Latest On: When Five Hundred Tigers Are Not Enough”
What do Swedish war booty, the Frombork Cathedral in Poland, and Napoleon all have in common? Answer: Nicolaus Copernicus. While much is known about the cleric and astronomer, the location of his burial site and the identity of his possible remains were cloaked in mystery. Over the last 200 years, many have searched for Copernicus’s grave including Napoleon in 1807. While it is known the astronomer was buried at Frombork Cathedral in 1543, there are over 100 unmarked tombs; as a result, searchers have walked away frustrated and empty handed. Continue reading “Wanted: The Tomb of the Father of Modern Astronomy”
When is an extinct subspecies not extinct? Maybe when it is not really a subspecies at all— The tiger subspecies Panthera tigris virgata, or Caspeian Tiger, was purported to have become extinct in February of 1970 when the last survivor was shot in Turkey. Leaving aside the hard to grasp idea that we might know down to the month when a species became extinct because someone shot the last one, it is clear that one tiger can hardly make little tigers by itself, so that subspecies was already doomed. Or was it? Continue reading “Caspian Tigers: Extinction Not Quite Forever?”
In my sophomore year at Iowa State University, I sat enthralled in a dark lecture hall as my animal genetics professor described studies done on wild populations of cheetahs that had found that the animals were so genetically similar that they could almost be called clones. Past bottlenecks in the cheetah population meant that and even though population numbers had rebounded, the individuals were so genetically similar that the effective breeding population was much smaller. I was hooked. A week later I changed my major from “Pre-vet” to Genetics. Continue reading “When Five Hundred Tigers Are Not Enough”
One of my jobs at Promega is to coordinate our Educational Resources Web, so I am constantly on the prowl for interesting stories that will provide fodder for a bioethics discussion, a writing assignment or a case study. Science does not exist in a vacuum, and including information that puts science in the midst of its societal context is an important part of science education. Continue reading “Science, History and Identity”