On a hot day, sometimes you just need to find a place in the shade.
The impact of human activity on bees is a hot topic right now, and often the news is negative. In a turnabout, Margarita M. López-Uribe, James H. Cane, and Robert L. Minckley used genetic markers to show how the native squash bee, Peponapis pruinosa, moved from Central America to the east coast of North America with spread of squash plants through human agriculture practices.
This short video summarizes their study.
Along with evidence that the distribution of bees followed the spread of squash crops, the scientists also found evidence that Peponapis pruinosa populations have gone through reductions in genetic diversity or bottleneck events.
As an aside, this is a prime example of how the use of traditional journalistic techniques (a news release) and social media can generate interest in studies that might otherwise languish inside the pages of a scientific journal.
What do you think?
Margarita M. López-Uribe, James H. Cane, and Robert L. Minckley (2016) Crop domestication facilitated rapid geographical expansion of a specialist pollinator, the squash bee Peponapis pruinosa. Proceedings of the Royal Society B, June 22.
(Public domain photograph of Peponapis pruinosa from Wikimedia)
Looking for ants? Sometimes it is only a matter of finding the right plant.
The umbel flowers of wild parsnip (Pastinaca sativa) might be a good place to look for different kinds of ants.
Wild parsnip grows in wet areas, such as along creeks or streams. It can also be found growing on roadsides. At four to five feet tall, the flowers are right at eye level for many people. Be careful when visiting the plant, however, because contact with the sap can cause burns to the skin when exposed to sunlight.
Ants, flies, wasps and other insects can be readily found visiting the large nectaries of open flowers.
Although these particular ants were fairly small, large ants such as Formica and Camponotus were also seen on wild parsnip flowers.
What are the ants doing on the plants besides collecting nectar? Wild parsnips are considered to be invasive weeds in many areas. Therefore, ants feeding on nectar might considered to be favorable if they interfere with the plants' success or might be unfavorable if the ants protect the plants from herbivores. Jing Yang and Dana Dudle from the Biology Department at DePauw University studied the effects of ants on the reproductive success of wild parsnip by excluding flying versus crawling insects from certain flowers. In their limited investigation they found no differences in plant fitness whether ants were present or not, but suggested further studies needed to be done.
Regardless, if you are interested in watching ants you should keep your eye out for wild parsnip flowers.
Ave you ever seen ants on wild parsnip?
When you are searching for ants, what plants do you look for?