Malaria draws mosquitoes to infected humans, and vice versa 

Sarah Zhang at the Atlantic writes about an interesting new discovery: The molecule that draws mosquitoes to infected humans, and causes infected mosquitoes to be more hungry for blood, known as HMBPP:

The discovery came by accident. Ingrid Faye, a molecular biologist at Stockholm University, was curious about a particular molecule made by malaria parasites called HMBPP. She wanted to drill into the details of how HMBPP affects mosquito immune systems, but her team ended up noticing some behavior too odd to ignore: The mosquitos—specifically, the species Anopheles gambiae they were studying—would go crazy for human blood with HMBPP. “The difference it made was just astounding,” says Faye. When given a choice between normal human blood and that either laced with the HMBPP or infected with malaria parasites, almost all the mosquitoes went for the latter two.

Source: The Parasite That Lures Mosquitos to Humans – The Atlantic

We sleep to forget what happens during the day

Scientists have put forth the idea that one of the potential reasons we sleep is not to regain energy, but to sort out your brain so it’s good for the next day, as Karl Zimme writes for The New York Times:

A pair of papers published on Thursday in the journal Science offer evidence for another notion: We sleep to forget some of the things we learn each day.

In order to learn, we have to grow connections, or synapses, between the neurons in our brains. These connections enable neurons to send signals to one another quickly and efficiently. We store new memories in these networks.

I’m posting this right as I go to bed, so I’ll tell you later today how my synapses are.

(via Nextdraft)

Giving a voice to mummies

Anna Barney, Heritage Daily:

To know how Ötzi the Iceman sounded we need to know how long and how thick his vocal folds were – that tells us about the natural pitch of his voice. We also need to know how long his airway was and about the cross-sectional area to work out the resonance frequencies. His tongue and lips will have been preserved in one particular position which will only give us information about a single vowel sound. So if we are to work out how he sounded for other vowels we also need to know a bit about the size of his tongue and where it joined to his windpipe. Knowing this allows us to work out the other possible tube-shapes he could make and calculate their related resonances.

But how can you actually work all this out? It’s pretty simple, all you really need is a CT scan, which uses X-rays to create detailed images of the inside of the body. This allows us to measure all these anatomical dimensions. We can then use that information to make a computer model to synthesise what his voice might have sounded like.

It’s a shame that, as the system relies on soft, fleshy tissue of mummies, we’ll never hear Lucy’s (Previously) voice.

The final moments of Lucy

Anyone who took Biology in high school and learned about human evolution probably learned about the fossil affectionately called Lucy (scientifically called Australopithecus Afarensis). To put it very simply why Lucy was special: while she had the very small brain that we associate with an ape, she also showed many trends similar to bipedalism and our modern form of upright walking. But she’s a fossil, so she died, right? And have you ever wondered how? Ed Yong at The Atlantic gives it to us:

Here’s their best guess about Lucy’s last moments. She fell, feet first and arms outstretched. The impact broke both of her legs and twisted her body to the right. Her knees hit the ground, both breaking. Her right hip landed—more fractures. When her arms hit, they broke too, the right more seriously than the left. The right shoulder blade pushed her collar bone into her first rib, breaking them both. The final collision between her torso and the ground added more fractures to her hip, ribs, vertebrae, skull, and jaw. Body broken and organs presumably damaged, she would quickly have died.