If you think spring has been arriving earlier, you’re right: although nothing has changed in Earth’s orbit, and the balance of day and night hours has not shifted, the warmth associated with spring has been tiptoeing in sooner than it did 40 years ago, Cornell University scientists reported in 2004 in the International Journal of Biometeorology (see also my June 4 column on how climate change is affecting airborne plant allergens). Models of climate change predict that the planet’s polar regions will feel the impact of a warmer world more than other regions, and an earlier spring, it now turns out, is no exception: in the arctic, winter is giving way to spring weeks earlier than it did just a decade ago, scientists report in Current Biology .

“Arctic environments are and will be exposed to the greatest warming,” says Toke T. Høye of the National Environmental Research Institute, University of Aarhus, Denmark, who led the research. “Our study confirms what many people already think, that the seasons are changing and it is not just one or two warm years but a strong trend seen over a decade.”

The scientists studied the timing of such signs of spring as when plants bloom, butterflies emerge and birds undergo seasonal migration. Most such studies had focused on seasonal shifts in temperate regions, finding that spring has advanced 2.5 days per decade for European plants and 5.1 days per decade for animals and plants globally over the last 40 or so years.

“I feel your pain” is often meaningless pablum, but for some people with unusual brain wiring it is literally true.

People with a condition called mirror-touch synesthesia experience the sensation of being touched when they see someone else being touched. (In other forms of synesthesia, one sensory experience—feeling or hearing, for instance—triggers a wholly different one, such as seeing. As a result, the estimated 1-in-200 people who have synesthesia see particular colors when they hear particular musical notes, or see shapes when they process aromas, or always see specific letters or numbers in the same particular color, so that a P is always lemon yellow and a 5 always mauve. One synesthete told me that a roast chicken in citrus sauce is perfectly cooked when it "looks pointed.”) A new study finds that mirror-touch synesthetes have an unusually strong ability to empathize with others. More than a mere curiosity, the finding hints that empathy may arise from the brain’s ability to feel what it sees.

In 2002 scientists established, with brain imaging, that synesthesia arises from crossed-wiring. In synesthetes who see colors when they hear spoken words, the brain region that processes color in standard brains is also activated by words. Neuroscientists’ best guess is that synesthesia arises when the developing brain fails to prune the millions of extra connections, or synapses, that we are all born with and that standard brains eliminate in childhood; the result is a rich web of circuitry that connects touch areas and visual areas, or sound regions with vision regions, or other sensory combinations.