Venoms have evolved independently in several different
vertebrate lineages: in snakes and lizards, and in
the platypus, and in one other mammal.
What are the transitional stages for venom to appear?
How would the appearance go in, say, a population of people?
2009-04-01 Wednesday 17:41:46
Yesterday's solstice was the day when the northern hemisphere
gets less solar irradiance than any other. In most countries this
is "midwinter," but in the United States it's "the first
day of winter." When did this label change?
2008-12-22 Monday 06:58:50
Supposedly volcanism on Io is caused (or enhanced) by tidal heating
from Jupiter. What power does tidal heating dissipate in the
2008-10-23 Thursday 13:03:59
What makes glassy smooth patches on the surface of a larger body of
water? Why are the patches partially stable against rippling from
2008-10-23 Thursday 06:05:41
The Economist claimed that an oil price spike on September 22 (or
thereabouts) was a quirk of timing, due to some minor supply quirk
that happened to happen in the last couple days to fill contracts
for delivery October 1. When I hear about "the oil price"
on the news, what am I hearing? Is there information in the spread
between short- and long-term prices that isn't reflected in
either market alone?
2008-10-03 Friday 00:57:19
You can't interact with a physical system without disturbing
it, though you can ignore the disturbance in the limit where
ħ is small. Similarly, you can't interact with a market
for some product (by asking or buying or offering or selling)
without affecting the "market price" seen by others, but
you can neglect that change unless your exchanges comprise a large
fraction of the market. There is some correspondence here. Clearly
it'd be easy to take this correspondence as justification for
saying some really dumb things. Are there any useful insights
2008-09-26 Friday 14:50:23
There are 146×106
Powerball lottery tickets. If
the jackpot goes above about $120M, the average payoff on a single
ticket is more than a dollar. Of course, buying two
doesn't double the payoff: you can't win the jackpot twice.
If an ensemble of catious statisticians only played the lottery
when the payout was positive, what fraction would actually come out
2008-09-24 Wednesday 09:39:54
Political polls of a thousand people's opinions are reported
with an uncertainty of 3%, which is roughly 1/√1000. Is this
mostly Poisson counting? An election is just a larger statistical
sample with a different set of biases. What is the margin of error
on an election?
2008-09-20 Saturday 21:38:27
NPR has reported twice in the past couple weeks that NASA managers
have expressed anxiety about the upcoming mission to service the
Hubble telescope. Because the Hubble orbits further above the
atmosphere than the ISS, where most shuttle missions have gone
recently, the chance of the shuttle colliding with some space junk
is "double" that on recent missions. Doubled from what?
2008-09-20 Saturday 08:28:36