Now, there are some people I know who’d argue that it doesn’t really and you’re best of actually not cleaning your skin too much because it sort of messes up the balance of it.  But I should think that skin scrub helps to get rid of dead skin and the surface grease and yuck and the things that block your pores that cause spots.  But then some people might argue that it actually dries your skin out too fast and takes all the natural oils off it.  So, it’s meant to help that way but whether it really does is for discussion.

The fundamental difference between green and black tea is that black tea is actually fermented.  So, it’s probably got some different chemicals in there almost certainly, different things going on.  So, that remains a bit of a question mark, but maybe that’s something they might look at in the future and I think there are good things about drinking black tea as well. 

There’s probably two reasons for this.  The first one is that the lemon is acidic and so it’s affecting the pH of your tea and it may be that it’s causing changes in the chemicals that are in your tea and making them change to a different colour.  So, like you can make indicator paper and change colour with different acids or bases and I think also, certainly down the south, we have a lot of limescale which is calcium carbonate in our water and it can make your tea cloudy.  So, if you put in an acid, it will help to dissolve the calcium carbonate in it so it makes it go clearer.

Now, there isn’t really a special purring organ in a cat.  It’s simply a very fast movement of their voice box.  So it’s fast twitching of the muscles in their larynx which rapidly kind of flap up and down something called the glottis.  That’s some little flaps inside your throat, and it causes air vibrations when you inhale and exhale.  And interestingly, a fact for you is that tigers, lions, jaguars, and leopards can only purr when they’re breathing out!

Now, this is a really good one because basically it’s the same energy that we use for all our metabolism.  That’s the energy created by eating fuel, metabolizing the food that we eat, turning into energy in the form of ATP within ourselves, it generates energy.  But actually, the stuff that makes the heart beat is electrical impulses from our nerves and then the electrical impulses in the muscles and interestingly, you can take muscle cells out of the heart.  You can grow them in the lab and they’ll still beat within the lab because basically, you have this kind of feedback loop that just keeps on beating, but they get all out of rhythm and you need the nervous energy, the nerve impulses to get them all beating together.

We put this to Rebecca Kilner, Department of Zoology, University of Cambridge...

I don’t think there’s a consensus in the scientific literature on this, but there are a couple of good ideas and the general theme is that if it takes two to rear babies effectively then you stick together with the one that you already know.  So, that might be the case for example if nest sites are in short supply and it takes two of you to defend the site, then it’s better to stick with the team-mate that you’ve got than to change for the next season.  Similarly, if you’re feeding your chicks on complex food that’s hard to forage for, it’s better to stick with an experienced bird than to try your luck with a potentially naive individual.

We posed this question to Rebecca Kilner from the University of Cambridge...

It’s not just confined to the birds and that’s because universally across the animal kingdom providing child care is costly.  So, that means there’s a tremendous incentive for individuals to steal childcare from other individuals.  We know that that happens in fish - for example, there’s a cat fish that steals parental care from fish that brood their eggs and fry in their mouth.  So, it takes care to get its host to swallow its fertilized egg and then the cat fish develops within the mouth of the host fish and it eats all the other eggs and fry in there and grows spikes so that the host doesn’t swallow it and then, finally, is spat out when it’s completed development.

There are also some equally horrible insects that steal parental care from ant colonies. Say for example, the cuckoo butterfly, is so named because it induces ants to pick up its caterpillar and carry it back to their colony where they treat it like a giant member of their own colony and they carefully nurture it for between 11 months and 2 years until it’s grown large enough to pupate and then it becomes the adult butterfly.  So yes, it’s widespread in the animal kingdom.

We posed this question to Rebecca Kilner from the Univesity of Cambridge...

There are some host species that are confined to Australia, as far as we know at the moment, who can recognize the cuckoo chick in the nest.  And what happens here is that, recognition typically takes place four days after hatching and the birds simply stop feeding the chick in the nest, even though it’s alive and well and healthy and begging for food.  Something happens that makes them realize it’s not their own and they give up on the chick and they take the nest apart even thought the chick is still sitting in there and still alive, and they build a fresh nest next door and eventually, the cuckoo chick starves to death and the meat ants move in and dismember the corpse and carry it back to their own nest

We put this to Rebecca Kilner, Department of Zoology, Cambridge

Yes, that’s right.  You’re leaving them with the responsibility of bringing them up but at the same time you’re avoiding all the costs that they incur in rearing children.  So, it makes sense that these parasites have evolved.