Natures wonders: adapting to climate change (Introduction)

by David Turell , Tuesday, January 28, 2020, 18:16 (1759 days ago) @ David Turell

Caterpillars of the corn borer moth are emerging three weeks sooner as the Earth warms, managed by genes:

https://www.the-scientist.com/notebook/circadian-clock-genes-help-a-crop-pest-adapt-to-...

"Each winter, after going through their last molt before becoming pupae, corn borers (Ostrinia nubilalis) enter a dormant state of activity known as diapause. To survive this vulnerable time, the larvae hide out someplace where they won’t be disturbed. For corn borers, that place is inside the stalks of the plants, which also serve as their primary food source when they wake up in the spring.

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"To find out how O. nubilalis might be adjusting its emergence time, the group recently scanned the genomes of larvae in five populations—three early-emerging and two late-emerging. The team found that larval emergence time was linked to variation in two genes known to be involved in circadian rhythms. One is period, or per, a gene that regulates sleep-wake cycles in Drosophila and has been linked to seasonal timing in many other insect species. The other gene, Pdfr, produces a receptor that binds to a neurotransmitter called pigment-dispersing factor, which in Drosophila helps to regulate the activity of clock neurons in the brain. Dopman and his colleagues speculate that variation in the sequences of these two genes could provide a way for corn borers, and perhaps other insects as well, to adapt to changes in season length. (my bold)

"This paper is incredibly interesting and important because it sheds light on the molecular basis of differences in seasonal responses,” says Megan Meuti, an entomologist at Ohio State University who was not involved with the study. The fact that the genes are already known to be involved in circadian rhythms suggests “that the differences in the sequences of the clock genes are not only affecting seasonal responses, but also daily responses as well.”

"Daniel Hahn, an evolutionary physiologist at the University of Florida, adds that while previous research has focused on how circadian clock gene polymorphisms are associated with the timing of insects entering dormancy, this new study shows that such variation is also “associated with when animals are going to come out of dormancy. That’s a completely new facet that nobody’s been able to do before.'”

Comment: We all know that organisms respond to temperature and light changes. Temperature response changes are shown by deciduous trees leafing out in Spring and we all recognize circadian rhythms in our sleep patterns. This obvious finding shows genes in control, as expected. The genes follow instructions after receiving the stimuli indicating changes. Note my bold. Shapiro's original bacterial discoveries at work in more complex organisms, just as he predicted!