Sunday Science Poem: The Irreversibility of Time

Czesław Miłosz’s “This World” (1994)

Telomere_capsIt’s a question you’ve certainly heard before – the laws of physics work just fine when you run time backwards, so why, in the real world, does time only go forwards?

Run a movie backwards, and what you see could never happen in real life: a diver never leaps feet first out of the pool onto the board, while drops of water fling themselves back in. But, as Richard Feynman explained, at the level of atoms and molecules, there is no reason why running the film backward should be absurd – our laws of physics say time is reversible at the microscopic level. Feynman argued that time’s forward motion was a macroscopic phenomenon, rooted in the universe’s relentless increase in entropy. Physicist Lee Smolin has pursued a similar (but in many ways a radically different) idea – the forward flow of time is a consequence of a network of relationships in the universe. He may be right, but for the time being, why time is not reversible is still a deep mystery.

Physics isn’t the only place where reversibility appears to be a mystery. Why isn’t life reversible? Aging and death seem inevitable for us individually, but with each birth, the clock is reset. Biological time is reversed. How is that possible?

We don’t really know. Before your children are born you age twenty, thirty, or forty years. Your DNA has been copied and recopied, accumulating damage, telomeres have shortened, and your cells are on the way towards senescence, and yet each newborn gets a fresh start. Amazingly, each successive generation of children is not born ever more prematurely aged. If the clock can be reset for our germ cells, why can’t we reverse biological time in the rest of our cells? Continue reading “Sunday Science Poem: The Irreversibility of Time”

Science Caturday: The Search for Bigfoot

bigfoot-yeti-ha-ha-ha-ha-ha-hoo-is-

Late last year, a group of scientists led by Dr. Melba Ketchum announced that they had sequenced the genome of a bigfoot, (also known as sasquatch or yeti), a furry, mountain-dwelling creature generally considered mythical. Not surprisingly, most mainstream scientists questioned Ketchum’s paper on the “Bigfoot Genome”, which, after being rejected by all the peer reviewed journals in the field, was published in De Novo, a brand-new journal which has published nothing else since.  The paper asserts that bigfeet are hybrids, the product of humans interbreeding with a still unknown species of hominin.

aaargh

A few months after the findings were released, John Timmer, the science editor of Ars Technica, wrote an article which systematically reviewed and explained the weaknesses in Ketchum’s paper.  Timmer spoke extensively with Ketchum, who, while admitting that some of her data didn’t fit a standard scientific model, claimed that she was confident in her knowledge that bigfeet exist – because she’s seen them.  Apparently they are “very fast” and curious about people. (Have I convinced you to read this article yet? You really should.)

catsquatch

Now a British scientist has come forward with more exciting news for cryptozoology fans.  Oxford University geneticist Bryan Sykes recently reported the findings of a project which tested hair and tissue samples that people claimed belonged to bigfeet, yetis or sasquatches. According to Sykes, DNA from two hair samples from the Himalayas matched the genetic signature of an ancient polar bear jawbone that was found in the Norwegian Arctic in 2004.  Although intrigued by the possibilities, most scientists in the field are withholding judgment until Sykes’ data are published and subject to peer review.

refuses

So maybe bigfeet are the descendants of prehistoric polar bears. Or maybe they’re half-human. Or maybe, just maybe, they’re cats. Nobody has tested the DNA yet, but the visual evidence is strong.

All photos via Cheezburger.com

Your Cheating Data

What makes scientists cheat? It’s cheating week over at Pacific Standard, and in my contribution, I talk about why scientists cheat.

I come up with three reasons:

1) It’s easy. So much of science is built on trust; generally, nobody comes into your lab and checks your notebook, equipment, computer code, or raw data. This is true of PIs as well – they trust that their grad students and postdocs are not faking their data.

2) There are (some short-term) incentives to cheat in science. In today’s hypercompetitive scientific community, there can be great pressure to cheat when you think your future in science is threatened. However, I think the long term incentives don’t favor cheating. Most serious cheaters seem to be caught quickly, the risks are huge, and the benefits of cheating scientists are more ephemeral than the benefits of many other types of fraud – scientists aren’t stashing laundered money away in offshore bank accounts.

3) When the data doesn’t go your way, it can be hard to accept that your idea is wrong. So much of science, especially experimental science, is a matter of judgment – what anomalous data is significant, and what data is simply a screw-up. Scientific publications by necessity are a selection of the work done by the authors, not a report of everything they tried. There are moments in every scientists career when some idea you knew just had to be true turns out to be wrong. Some cheaters are scientists who can’t deal with being wrong.

Meet the Mimic Octopus

xkcd (#928) by Randall Munroe (CC BY-NC 2.5)

The mimic octopus needs no introduction, but watch these videos to have your mind blown.

This is insanely beautiful and reminds us that humans are boring.

Also, you know you’re the business when you start mimicking a fish and some other fish mimics you and acts like your sidekick.

“Meet the…” is a collaboration between The Finch & Pea and Nature Afield to bring Nature’s amazing creatures into your home.

Political Polarization

Elkanah Tisdale, 1812 (Public Domain)

The current levels of political polarization and partisanship, which we are keenly aware of in the wake of the US Federal Government shutdown, get blamed on many factors, especially the bogeyman of new technology, the internet and social media.

Political critic Dan Carlin makes the point in his most recent Common Sense podcast (“The Shutdown Sideshow” at about 8:30) that increased political polarization should be an expected consequence of increased gerrymandering. In gerrymandered voting districts engineered to effectively guarantee the victory of a particular party, the winner of the election is primarily determined by the party primary elections. The winner of the party primaries is determined by each party’s “base” voters.

The inevitable result of such a system is the election of progressively more extreme politicians selected by gerrymandered districts, which effectively cut the majority of moderate voters out of the process. Responses to the activity of these politicians would then drive polarization among voters.

Is Dan Carlin right on this one? I cannot say for certain, but after five minutes of thought, it seems like increased political polarization is the expected consequence of an increasingly gerrymandered system, with or without modern communication technology. The burden of proof, therefore, falls more heavily on those arguing that it is the result of some other factor (eg, internet) or that political polarization has not increased.