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TED: Visualising data
TED talks are cool. I remember seeing this guy’s book in a shop – and not buying it. I love his point, I draw out information myself for revision times.
One thing though … what if, what if all this where online complete with links to sources and further information? Now that’d be what I’d call sexy.
The Amazing World of Hummingbirds (Part II)
The Cost of Sexual Selection
Hummingbirds are amazing fliers. They’re fast and agile. Some species have extremely long tails such as the Red-billed Streamertail, Trochilus polytmus(image on left below).
In species where females investment into offspring is larger, they choose their mate. Thus in many bird species, males compete with each other to be the “prettiest” and in some birds this means having a long tail. This is called sexual selection. (That long tails are selected for by females has been shown in some bird species.)
However, it has also been shown that an overly long tail decreases fitness in some species because a long tail decreases flying ability. If a birds tail is so long that it will die from other causes, such as starvation or predation, because it cannot fly well enough, tails won’t get longer. An equilibrium is reached.
In hummingbirds, where flying seems such an exquisitely honed, perfectly executed skill with amazing accuracy and power, wouldn’t long tails be really in the way? Presumably not, since these animals have them. Therefore a team of researchers set out to do experiments on hummingbirds to work out what the cost of a long tail for flying is. Apart from the Red-billed Streamertail, they also used Anna’s hummingbird, Calypte anna (left image below).
The Amazing World of Hummingbirds (Part I)
Hummingbirds in slow motion
Check out this awesome "behind the scenes” video of hummingbirds. Contains some awesome footage. The full length video is located here but unfortunately I cannot watch it where I am so I don’t know how awesome it actually is.
Use this video to get in the mood for some more exciting info on hummingbirds coming up (hopefully) soon!
Cool New Pictures of Embryos
My chosen speciality is Developmental Biology so naturally this video fills me with excitement.
But this is not only about some pretty cool images but also about the technique. There’s a paper in Science that’s all about taking images of embryos and measuring them. It’s all very technical but it comes with some cool computer generated images made from these measurements.
Olivier N, Luengo-Oroz MA, Duloquin L, Faure E, Savy T, Veilleux I, Solinas X, Débarre D, Bourgine P, Santos A, Peyriéras N, & Beaurepaire E (2010). Cell lineage reconstruction of early zebrafish embryos using label-free nonlinear microscopy. Science (New York, N.Y.), 329 (5994), 967-71 PMID: 20724640
The many (scientific) uses of penguin poop (Part III)
How hard does a penguin push?
Remember to read the newest and indeed first edition of the Carnal Carnival featuring many other stories about poop!
I’ll admit, I didn’t get the idea to post about penguin poop from the cool and well popularised study on tracking them from space. I got it from a very cool talk by Nathan Myhrvold. This is a guy who got rich working for Microsoft and then quit in 1999 do do random stuff with his money. Like take pictures of whale sex, buy T.Rex skeletons and laser mosquitos to help prevent Malaria. However, he’s not an author on this study so no more shall be said about him now. For more information check out this TED talk.
What’s this all to do with penguin poop? Well, he mentions a paper on the forces involved in penguin pooping. Because penguins are protected you cannot just go and measure the forces on a wild penguin. Instead, the authors relied in photographs. They used the previously mentioned Adelie penguin and the closely related Chinstrap penguin (picture below from wikipedia) again both of the genus Pygoscelis.
The many (scientific) uses of penguin poop (Part II)
Tracking penguins in time
Having established where these awesome, possibly cuddly, penguins are, it is time to turn out attention to their history. This is going to be a relatively short post based on a very short article.
Gentoo penguins (from Encyclopaedia Britannica)
Historical records are limited especially concerning animals in remote habitats. If we want to know how many of them there where at a specific point in time, we’re going to have to resort to different measures. That’s what some researchers from the University of Science and Technology in China did.
The many (scientific) uses of penguin poop (Part I)
Tracking penguins in (& from) space
Penguins are charismatic animals with a large role in popular culture. They are seen as cuddly (though personally, I think that penguins are from the dark side). Regardless of personal inclination regarding cuddliness, it is easy to see that penguins are unique animals. Something your average penguin fan will think of less often are penguin droppings. These are sometimes also referred to as guano, meaning they have a high concentration of certain elements such as nitrates and phosphates making it useful as a fertilizer (e.g. bat guano is often mined though this practice is controversial). However, penguin droppings, especially those from flagship-species such as the Emperor penguins are hard to harvest. However, penguin droppings have other uses which inspired this series of posts, here’s part I on tracking penguins in (& from space).
Emperor penguins, adult among chicks (from Telegraph.co.uk)
Of Man and Museums #3: The Natural History Museum (part 2)
The next exhibit I want to mention in these musings on the NHM London is the Mammals Gallery (blue whale hall). The life-sized model of a blue-whale is well known and definitely dominates the room, perhaps a little too much. The first impression I got when entering the hall was how crowded it was. This was partially due to many people in the popular gallery and having to narrowly avoid being flattened by push-chairs. However this was not the only cause of the feeling of claustrophobia I got.
Of Man and Museums #2: Natural History Museum London (part 1)
As I mentioned in the post about the Neanderthal museum a few days ago, I also visited the Natural History Museum in London. My impressions were varied. The museum was overcrowded, noisy and full of screaming, running schoolchildren, pushing everyone around with their backpacks. Not a good start. (A warning now: I will say few good things in this post but those that I do mention, I mean. Don’t be fooled in thinking the museum is not worth a visit because it most definitely is.)
The shot below was taken in the entrance hall. The gallery in the picture is on evolution. I’m sure it’s a nice gallery but it was being redone. There was a big black box in the middle of it. The nicest part of it where the skeletons of monkeys hanging above. I could find no plate identifying them but that could have been lost in the crowds and refurbishing.
And you know, it’s perfectly acceptable that a gallery gets refurbished. So I wandered on, fighting my way through the masses to the Dinosaur exhibition. And what was there to greet me? Apart from a too dark gallery, some technical gimmicks and too many people? Some more refurbishments. This caused the back exit of the gallery to be closed so that you had to fight your way back through the crowds to make your way out of the middle exit. Not great if there’s crowds around already. Should I bother mentioning the fact that the focus was not on fossils? Fossils where either not lit well enough (for example the replication of a fossil bed in which I could make out just about nothing) or they where mounted too high. Few where available for nice viewing.
Note that on the top gallery there’s also the “tree-gallery”. This is basically a ceiling art-work. It’s a slice through a tree. Stuck to the ceiling. The only other thing in the ceiling is Ida. ‘Nuff said. It’s a nice, light empty room with benches. I had a rest here. There’s also a video of the relevant tree-felling in the gallery next door but the general background noise was too distracting and there were no benches in front of the tv.
Also up here are statues of Huxley (‘Darwin’s bulldog’) and Richard Owens (the “inventor” of dinosaurs), similar to the statue of Darwin in the entrance hall that everyone knows but more hidden. Most people walk past them without seeing them.
Okay, on I go to the marine reptile gallery. That’s bound to be a good one. And it is. It’s basically a long wall full of marine reptile fossils. Mainly ichthyosaurs (my favourite!!), some mosasaurs and some pleisiosaurs. There’s the pregnant ichthyosaur fossils that I’ve read about, there’s the skeletal eye ring. Most people just stomp past it. There’s no colours, no big panels explaining things. Sure, the gallery could use some revamping, some explanations wouldn’t be amiss and some fossils are so high up you can’t really see them, especially with the reflections from the light. But the fossils speak for themselves to me. This has to be my favourite part of the museum.
On I went, through the birds gallery. This contains a nice historical case showing what galleries in museums used to look like. I would have liked to study it in more detail but was once again cowed by people wanting to take their picture with the case.
Also here is the entrance to the special exhibition “The Deep”. I had already seen this exhibition in Frankfurt last year and it is excellent. I didn’t go to see it again for time and cost reasons but it’s definitely worth it.
And yes, I’m aware I harbour an intense hatred for crowds. Sorry.
Next time: squid, whales and the internet.
Listening to: If a song could get me you – Marit Larsen
Further posts about museums:
Newsflash: a possible mechanism for Parkinson’s disease
Mutations in the allele LRRK2 is used to test for Parkinson’s disease. It’s a gain-of-function mutation that causes familial as well as sporadical Parkinson’s. But so far, no one really knew what LRRK2 actually does. Now, a new study shows that pathogenic (=disease causing) LRRK2 prevents the correct function of certain miRNAs.
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