Science roundup: old Grand Canyon, ringed Saturn moon, hereditary happiness

Grand Canyon 3x older than thought

The western section, at least, of the Grand Canyon has been redated to an age of 17 million years, or three times older than the previous 6my estimate. Scientists from the University of New Mexico used uranium-lead radioactive dating to get new ages for sediments on Grand Canyon cave walls.

Ring around Rhea

Evidence from the Cassini spacecraft appears to show a ring around Saturn’s second-largest moon, which lies within the planet’s magnetic field.

Happiness propensity strongly hereditary

In what is somewhat of a “no-duh” report, given the amount of research on the heritability of depression and other mental health issues, British and Australian researchers claim about half of a tendency toward happiness is heritable.

That said, the story needs a couple of caveats.

First, note that I said “tendency toward happiness,” and “happiness propensity” in the subhead.. The actual story, showing that even AP or big newspaper writers who cover science stories oversimplify human biology pieces into “nature vs. nurture” rather than “nature via nurture” for the true pattern of how genes and environment interact.

Also, on personality traits, we know that maternal stresses can affect the prenatal womb environment enough to cause a propensity toward anxiety, among other things. And, no personality assessment today is able to factor out this environmental influence in order to not falsely ascribe its effect to genetics. Of course, identical twins are in the same womb; a fair amount even share at least the same placenta and some even share the same amniotic sac, depending on how late after fertilization the original zygote divided. So, at least part of that claimed “50 percent genetic” isn’t so; 40-45 percent is more likely the reality, which is still big.