Web edition: March 20, 2013
Print edition: April 6, 2013; Vol.183 #7 (p. 31)
Get a grip
The article “Pruney fingers get better grip” (SN: 2/9/13, p. 11) indicated that skin wrinkling in response to extended exposure to water was the result of constricting blood vessels. I was waiting to read about the possibility that this was the body’s response to prevent heat loss. Water has a high heat capacity, and therefore I might expect that blood vessel constriction is to minimize heat transfer from the body to the water. Perhaps the wrinkling is a secondary, albeit advantageous, effect.
Jim Marrone, Pinole, Calif.
As a conservation biologist, I am wary of claims extrapolated from a survey of previous studies “Cats claim billions of bird and small mammal victims annually,” (SN: 2/23/13, p. 14) — studies which themselves are often incomplete and/or estimate data because gathering accurate numbers in the field is difficult. If the best that the Nature Communications paper can report is that North American feral cats kill between 952 million and 3.1 billion birds per year, somebody needs to get back in the field.
Alice Cascorbi, Portland, Ore.
My opinion: Feral cats, or domestic cats that are allowed to roam outside, are introduced vermin just as are Burmese pythons in the Everglades or brown tree snakes on island bird sanctuaries, and should be eliminated in the same way. (No doubt this will provoke plenty of posturing, irrational outrage from toxoplasmotic “cat lovers.”)
Steve Palmer, online comment
I cannot help but wonder how the estimated deaths of birds caused by domestic cats compared with the death of birds through human development — high-rise cities, neat tidy suburbs, paving, deforestation and agriculture.
Evelyn Haskins, online comment
Squeeze on cancer
Regarding “Pressure keeps cancer in check” (SN: 1/26/13, p. 8), how do you put pressure on a single cell? And does the researcher believe the pressure from exercise may have the same effect?
Joe Lucier, via e-mail
The researchers built a special apparatus to supply short pulses of pressure to cells from all sides at once. They used many cells, not just one — important because the pressure caused the cells to cozy up to each other and reestablish communications. Exercise or massage doesn’t apply the same type of pressure and probably won’t do the same thing. Once scientists identify the molecular events turned on by pressure, they may be able to trigger those events chemically, such as with a chemotherapy drug. — Tina Hesman Saey