Watch this video of a cheetah running at full speed, taken with a high-speed camera. Note particularly how the head is held so rigidly fixed while the rest of the body goes up and down, no doubt as a result of the need to focus so intently on its prey. [Read more…]
The speed of light is the biggest barrier to the dream of intergalactic travel and the chance that we might ever encounter extraterrestrial intelligent beings. Faster than light travel has been the Holy Grail of scientists and science fiction writers and indeed of anyone who dreams of visiting distant stars and galaxies. After the recent unfortunate premature hype over the claims of faster-than-light neutrinos, I thought that we would not hear of such claims for some time. But it appears that scientists at NASA have been working on an idea that would enable faster-than-light travel. [Read more…]
The theory of evolution by natural selection says that changes come about incrementally, as a result of the long-term consequences of small selection advantages for favorable traits. The selection advantage is measured by differential rates in the production of offspring. If organisms with a new and favorable trait produce 101 offspring for every 100 produced by the older forms, the selection advantage s is said to be 0.01. The changes produced by even such a small reproductive advantage can be quite dramatic. If we start with a trait that is present in just 0.1% of the population and if this has a small selection advantage of size s=0.01, this variety will grow to become 99.9% of the population in just under 1,400 generations (in the codominant mode of selection) which is a very short time on the evolutionary scale. (Molecular Evolution, Wen-Hsiung Li, 1997, p. 39) [Read more…]
Gary Marcus predicts that in a few decades, we may all not only have the option of traveling in driverless cars, we may even be obligated to do so.
Within two or three decades the difference between automated driving and human driving will be so great you may not be legally allowed to drive your own car, and even if you are allowed, it would be immoral of you to drive, because the risk of you hurting yourself or another person will be far greater than if you allowed a machine to do the work.
The program Science Friday looks at what happens when we are placed in a situation where reality is at odds with what we see. Even when we know exactly what is causing the discrepancy, a sense of disturbing disorientation sets in. [Read more…]
There has been some excitement because Pat Robertson, of all people, recently told a viewer of his TV show that the Earth is much older than 6,000 years, and that Christians should stop trying to pretend that it is and that everything happened within that time. He says that if parents try to fight ‘revealed’ science (whatever that is) they will lose their children. He even talks about radiocarbon dating and fossils in support of his position! (Via Pharyngula.) [Read more…]
I am not a fan of practical jokes. They are often cruel rather than amusing and it is not fun when one person is the victim and is being laughed at by others. Sometimes they can be excused because they cause just minor embarrassment but this too is dangerous because what can seem like something minor to the perpetrators can be traumatic for the victim. [Read more…]
In yesterday’s post, I discussed how the changing demographics of the US threaten the future of the Republican party. While I focused largely on ethnicity, there is one other demographic where the party is getting trounced and that is among scientists. In an article titled Why Conservatives Turned Against Science Erik M. Conway and Naomi Oreskes lay out the figures. [Read more…]
Two dogs explain the different types of chemical bonds that form between elements.
My one suggestion for improvement is that the partner to a ‘cation’ should be a ‘dogion’ instead of the traditional ‘anion’.
(Via Maggie Koerth-Baker.)
Even though we were on the fringes of Hurricane Sandy, a massive pine tree in our backyard toppled over during the night, even though there was not much wind. We did not even hear it falling, suggesting that it fell over slowly rather than come crashing down, presumably because the cause was the soil being weakened by steady, but not heavy, rain rather than high wind. Fortunately it missed our house and garage and the neighbor’s house and garage and the main damage it caused was to the fence separating our two properties and to a smaller tree that was in its path. [Read more…]