News
A study on beetles has revealed why there are no longer 3 foot-long dragon flies buzzing around in your garden (as there were 300 million years ago) - and it's all down to oxygen. Alexander Kaiser, from Arizona's Midwestern University, together with his collea...
Archerfish, which knock their prey into the water with a well-aimed blast of water, tailor the power of their shot to the size of their meal, German scientists have found. Writing in this months edition of the journal Current Biology, Thomas Schlegel and his c...
Even though giant pandas are black and white, doesn't mean that they can only see in black and white - because this week we have news from scientists in America who discovered that giant pandas are not colour blind but can distinguish colours from greys. Angel...
The Devils Hole pupfish is one of the most endangered species of fish in the world, because in the wild the entire species lives only in a single rocky pool in Death Valley in California. Now scientists have discovered that the Devils Hole pupfish, a little in...
Questions

Some washing powder manufacturers are starting to recommend that we wash our clothes at 30 degrees centigrade instead of 40 degrees centigrade. I can see the energy benefits of that, but is 30 degrees hot enough to kill bacteria in the wash?
That's a really good point and there are a few things to bear in mind with this. The smells that you get on clothes aren't actually the bacteria on your clothes per se. What happens is that your body create the ideal home for bacteria to live. They live on dead skin and sweat that you squirt out onto the body's surface. They produce trace elements and chemicals and metabolites, which soak up into your clothes like blotting paper, and they're a bit whiffy. So your clothes don't necessarily smell just because they're contaminated. When you wash your clothes you wash out those substances and that's why they have a nice smell. The excellent point you've made is whether these temperatures are hot enough to neutralise any bacteria that may be on the clothing. This could be important if you're working in a hospital, I suppose. The answer is that there are a lot of detergents in washing powder and it's very alkaline as well. It can cause caustic burns if you put it on the skin. It would take some pretty hardy bugs to survive it, but some can. Things like mycobacteria that cause TB can survive in those conditions. You maybe should consider washing at higher temperatures if you think there might be bugs loitering on there.

What's glaucoma?
Glaucoma is another important condition of ageing. It causes a gradual loss of peripheral vision. The reason this happens is that the nerve is being gradually damaged and this usually happens because the pressure in the eye is too high. The treatment that we can give to try and prevent this from happening is treatment to lower the pressure either with drops or sometimes with operations.

Why can't I recognise a face that I've known for many years upside down?
I'm afraid I don't have a clue! Although what I can say is that although we can't do it and other animals like sheep and cows can't recognise other sheep and cows when they're upside down, monkeys can actually do it. So it would seem to imply that if you habitually hang upside down then it's something you can do. They've not looked at bat face recognition as far as I know!

My eyes often become watery for no apparent reason. Why do you think this is?
When you go out in the wind, it's a stimulus to tear production. Tears are quite useful because they keep the cornea, that's the front of the eye, moist. They keep the eye smooth and functional. But if you go out on a windy day, often you produce a few too many tears and they fill up the whole conjunctival sac and so you're looking through water. So I suspect that it's that: different conditions will bring it on.

My husband has recently developed a squint overnight. Why is that?
It's probably because one of the muscles is not working properly. There are six muscles and it's probably because one or maybe two of them are not working very well. So it could be a nerve being pinched somewhere, but as it happened overnight, it's more likely that a blood vessel blocked. So the supply to the nerve is damaged and the nerve doesn't work very well. Usually it will tend to recover in a few weeks.

Can bulls see red?
Yes, bulls can see red but they probably can't distinguish it from green. They only have one visual pigment in that part of the spectrum, which means that they can distinguish blue from other colours, but they can't distinguish red from green. They see the world like a red-green colour deficient person. So waving a red rag at a bull isn't a problem because it's red, but because it's moving. They're responding to the movement rather than the red, although they can still see the colour. They will just get confused between red and green rags.
Kitchen Science
Investigate some very strange bounces with a bouncy ball and a little grease
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