The physics of how cats drink

An unfunded, seemingly just-for-fun study of how cats drink was recently carried out. Results show that they only touch their the surface of their tongues to the water. They use inertia to bring the water into their mouths, closing their jaws before the counter-acting force of gravity takes hold. The rate at which cats lap matters, which is a testament to evolution, of course. Interestingly, one model the researchers used predicted that larger cats would lap at slower rates. It turns out that that is true. But what I find interesting is utilization of social tools by the researchers to find their results.

“It occurred to me that there were some interesting biophysics behind that process,” Stocker said.

So he borrowed a high-speed video camera from his lab and taped Cutta Cutta drinking. With several other curious researchers along for the ride, Stocker analyzed those videos, along with video collected from Zoo New England and YouTube.com videos of lions, tigers and other big cats drinking.

“It seems to be that this is the first study in Science that uses YouTube as part of the research,” Stocker said.

The model also allowed the researchers to predict that larger cats would need to lap slower to strike a balance between the inertia and gravity of the water picked up by their tongues. Sure enough, the videos showed that lions and tigers lap less than 2 times per second, about half the rate of domestic cats.

YouTube, Facebook, Twitter…like it or not, they and their analogues are the future. (And personally, I like it.)

The eye candy

It has recently occurred to me that I’ve been neglecting the Hubble eye candy posts. Well, I’m technically still doing that because this image (“Ring Nebula”) was taken with NASA’s Spitzer Space Telescope. But it’s still eye candy.

We are star stuff

I feel a good Carl Sagan video is needed every once in awhile in life.

Repost: Only in the light of evolution

There are two reasons I want to make a repost of a post from about a year and a half ago. First, it’s always interesting to go back and read old posts for me. From time to time I have no recollection of making a certain post, so when I see it, it’s almost like it’s brand new to me. I do happen to remember this one very clearly, but it is at least understandable why I was skimming posts from May 2009. Second, I average significantly more views now than I did a year and a half ago. I feel this post is a pretty important one, and now that more people can see it, I would like to throw it back up.

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I am following a specific chapter in Jerry Coyne’s Why Evolution is True.

The fossil record: We should see fossils in a certain order if evolution is correct. They should go from simple to more complex overall, and the fossils we see in the most recent strata should resemble extant life much more than the fossils we see in old strata.

We should also see changes within lineages. We should be able to observe instances of gradual change in species that eventually leads up to either current species or at least to the time of extinction for these species.

Here’s a simple timeline of life’s history. Click it.

What the evidence shows is gradual change. First we find simple bacteria which survived off energy from the Sun, then we see more complicated cells known as eukaryotes arise. (You are a eukaryote.) Next we see a slew of multi-cellular animals arise. They’re still simple, but much more complex than the original bacteria. A few million years later more complicated life arrives. Early (and simple) plants begin to take hold. Soon the fossil record begins to show more plant complexity with low-lying shrub such as ferns, then conifers, then deciduous trees, and finally flowering plants. Gradual changes occur in the oceans and fresh waters which lead to fish and then tetrapods (Tiktaalik comes to mind).

One of my favorite fossils is trilobites. They’re extremely common due to their hard bodies. In fact, even their eyes are well-preserved because of their hard mineral make-up. I personally recall entering touristy-stores seeing countless fossils of these guys in the mid-west to the west (which, unsurprisingly, was once a shallow sea). This image shows the different lineages of this organism. Studies show that the ‘rib’ count has changed over time in each individual species, often without regard to how the other species changed. Going back further, there is less and less divergence in each species. Eventually, as evolution predicts, they all meet at a common ancestor.

So naturally the next step is to find fossils which show more significant changes. Let’s take birds and reptiles. They hold similarities between each other, both morphologically (certain shapes and structures) and phylogenetically (genetic sequence). A good hypothesis is that they came from one common ancestor. If this is true, the links between birds and its ancestors and reptiles and its ancestors should lead to the same point. They do. Dinosaurs are the ancestors of both. The links between birds and dinosaurs are so incredibly well established that I’d prefer to not go over them in detail. But for starters, some dinosaurs sported feathers and claws and had the same proteins for the feather-making process as extant birds. The links between reptiles and dinosaurs is easier just on intuition, so I’ll leave it at that for now.

Other transitional fossils include the already mentioned Tiktaalik. A view of the history of life can be see here. This shows the change in head and neck structure. Recent research on long-ago discovered Tiktaalik fossils has shown the importance in the gradual bone changes in the neck. These changes – a hallmark of evolution – were important to the ability to turn its head. This is a hallmark because natural selection only modifies what already exists. This is precisely what happened.

Going further with this example, evolution makes predictions as to how early fish evolved to survive on land. If there were lobe-finned fish 390 million years ago and obviously terrestrial organisms 360 million years ago (which is what the fossil record shows), then if scientists are to find transitional fossils, they should date in between that time frame. There should be an animal that shows both features of lobe-finned fish and terrestrial animals. Tiktaalik is that animal. It has fins, scales, and gills, but it also has a flat, salamander-like head with nostrils on top of its nose. This is a good indication that it could breathe air. Its eyes were also placed there, indicating that it swam in shallow waters. Furthermore, it was lobe-finned, but shows bones (which eventually evolved into the arm bones you used to get out of bed today) that were able to support its weight to prop itself up. And of course, it dates to 375 million years ago.

Next, evolution says the fossil record should show recent fossils being more closely related to extant species than are early fossils. This is precisely what happens. Sixty million years ago there were no whales. Fossils resembling modern whales only show up 30 million years ago. So, again, evolution makes a predication: if transitional fossils are to be found, they will be within this gap. And so it is.

We begin with Indohyus. It was an artiodactyl. This is important because extant whales have vestigial bones which indicate that they came from this order: scientists expected to find this because, again, evolution predicted it. It should be of no surprise that this fossil dates to about 48 million years ago, right in the predicted gap. From here there is a gradual evolution shown in the fossil record which leads up to modern whales.

The queen joins Facebook

Facebook is one of the greatest tools with which the Internet Age has supplied us. One in every 14 people in the world use it; 90% of those in Indonesia have accounts. It is the reason I can talk about Mark Zuckerberg without linking to who he is. Facebook has become a part of life – whether young or old. And speaking of the latter, Queen Elizabeth has joined up.

Britain’s Queen Elizabeth has joined Facebook, adding a presence on the world’s most popular social network to the royal family’s accounts on Twitter, photo-sharing site Flickr and YouTube.

The British monarchy’s Facebook page (http://www.facebook.com/TheBritishMonarchy) does not allow users to “friend” the Queen or to send her messages, but offers updates on royal news and diary events.

By midday on Monday, a few hours after the page went live, 60,000 people had clicked to signal they liked it, meaning they will receive updates on the royal family’s activities in their Facebook news feeds.

The page does not display personal details such as the Queen’s relationship status, interests or political views.

Britain’s royal family prides itself on keeping up to date with new technologies.

I’m not sure the royal family can point to joining Facebook in 2010 and say they’re really on the technological ball, but I am glad to see more and more people joining the site.