Background
The authors write that "a variety of processes can enable organisms, including insects, to respond successfully to climate change (Stenseth et al., 2002; Bradshaw and Holzapfel, 2006; Parmesan, 2006)," including "habitat tracking, phenotypic plasticity and genetic adaptation." Evidence for the first of these mechanisms, in their words, "is becoming commonplace," as is the case with many species of butterflies that are "clearly responding with northern extensions in their range limits (Parmesan and Yohe, 2003; Hickling et al., 2006)," as well as with moths and other insects that "are moving up altitudinal gradients (Chen et al., 2009)." On the other hand, they say that "the extent to which changes in phenotypic plasticity are (or will be) involved in the numerous reports of changes in phenology (Brakefield, 1987; Roy and Sparks, 2000; Amano et al., 2010) is not clear." And they indicate that "there are as yet few reports of genetic changes within populations linked to climate change," although they note that "the pitcher plant mosquito, Wyeomyia smithii, showed a genetic response to climate change, which involved changes in sensitivity to photoperiod (Bradshaw et al., 2006)," which "could be detected over a period as short as five years."

What was done
Hoping to contribute to the search for genetic responses to climate change, Brakefield and de Jong report on the most recent data describing changes in a cline in the frequency of melanism morphs of the two-spot ladybird beetle, Adalia bipunctata L., along a transect that extends inland from the seacoast in the Netherlands.

What was learned
At the time of the beetle's first survey in 1980, the two researchers report that "the frequency of melanics increased over some 40 km from 10% near the coast to nearly 60% inland." Additional surveys in 1991 and 1995, as they describe it, "demonstrated some progressive change in cline shape," while new samples from 1998 and 2004 confirmed these dynamics, showing that "over a period of about fifty generations of the beetle, the cline had decayed rapidly to yield rather uniform frequencies of melanic morphs at around 20% along the whole transect by 2004." And they remark that "climate data and evidence for thermal melanism in this species support [their] contention that these dynamics reflect a dramatic example of a rapid genetic response within populations to climate change and local selection."

What it means
As for the significance of their findings, Brakefield and de Jong conclude their paper by stating that their study "adds to potential examples of how some organisms are likely to be responding to climate change through direct genetic responses within populations," which is something the world's climate alarmists are loath to acknowledge.

References
Amano, T., Smithers, R.J., Sparks, T.H. and Sutherland, W.J. 2010. A 250-year index of first flowering dates and its response to temperature changes. Proceedings of the Royal Society of London B 277: 2451-2457.

Bradshaw, W.E. and Holzapfel, C.M. 2006. Climate change - evolutionary response to rapid climate change. Science 312: 1477-1478.

Bradshaw, W.E., Holzapfel, C.M. and Mathias, D. 2006. Circadian rhythmicity and photoperiodism in the pitcher-plant mosquito: Can the seasonal timer evolve independently of the circadian clock? American Naturalist 167: 601-605.

Brakefield, P.M. 1987. Geographical variability in, and temperature effects on, the phenology of Maniola jurtina and Pyronia tithonus in England and Wales. Ecological Entomology 12: 139-148.

Chen, I.-C., Shiu, H.-J., Benedick, S., Holloway, J.D., Chey, V.K., Barlow, H.S., Hill, J.K. and Thomas, C.D. 2009. Elevation increases in moth assemblages over 42 years on a tropical mountain. Proceedings of the National Academy of Sciences USA 106: 1479-1483.

Hickling, R., Roy, D.B., Hill, J.K., Fox, R. and Thomas, C.D. 2006. The distributions of a wide range of taxonomic groups are expanding polewards. Global Change Biology 12: 1-6.

Parmesan, C. 2006. Ecological and evolutionary responses to recent climate change. Annual Review of Ecology, Evolution and Systematics 37: 637-669.

Parmesan, C. and Yohe, G. 2003. A globally coherent fingerprint of climate change impacts across natural systems. Nature 421: 37-42.

Roy, D.B. and Sparks, T.H. 2000. Phenology of British butterflies and climate change. Global Change Biology 6: 407-416.

Stenseth, N.C., Mysterud, A., Ottersen, G., Hurrell, J.W., Chan, K.S. and Lima, M. 2002. Ecological effects of climate fluctuations. Science 297: 1292-1296.