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Stuart Farrimond

Stuart Farrimond has written 255 posts for Guru Magazine

Insect fears: Where did we get our fear of creepy-crawlies from?

Spider on log, Dolly's, Brevard, North Carolina by Martin LaBar, on FlickrOf all the weird jobs in the world not to to do, being an entomologist – an insect expert – has to be at the top of the list. Few of us would relish the prospect of spending every working hour studying creepy-crawlies. Because for many of us, the mere suggestion of getting intimate with a mosquito or a bumble bee would be enough to bring us out in hives (sorry). But why do we have such a morbid hatred of these tiny little creatures – after all, what did they ever do to us?

When something scares us, our heart pounds, our palms get sweaty and we desperately try to get away. (Think: the woman standing on the table, screaming at the mouse in the old Tom and Jerry cartoons.) This primitive scaredy-cat reaction is part of what is termed the ‘fight or flight’ response: adrenaline surges around the body, blood flows to the muscles and our body prepares itself for action. We all have this biological response – and its necessary to help get us out of trouble.
It makes sense to get fired up if you’ve just stepped out in front of a bus. It makes little sense, however, to do the same if a spider has just crawled into bed with you. Strange then, that about one in ten of us have some kind of irrational fear. And arachnophobia – fear of spiders – and a phobia of insects are some of the most common.

While not all experts can agree, it seems likely that we have inherited such fears from our ancestors. Passed down through evolution, our forefathers would have relied on such simple, innate fears to help keep them from harm’s way. For example, a phobia of snakes would have prevented us from getting bitten, a fear of wolves would have helped prevent us from getting savaged, and freaking out at spiders would have stopped us getting poisoned by venomous ones.

Some phobias are ‘learnt’ through bad life experiences and many phobias can be ‘unlearnt’ through repeated exposure. There are however some ingrained fears that can’t be explained so easily. Clown phobia (caulrophobia), for example, is a particularly odd one – it’s pretty unlikely that our caveman ancestors faced too many sharp-clawed prehistoric jesters!

But then again, perhaps we are all just born with an aversion to bad humour.

A man walks into a bar holding a piece of asphalt. He says, “a beer please and one for the road!”

I rest my case.

Answer by Dr Stu

Image Source: Spider on log, Dolly’s, Brevard, North California by Martin Labar, on Flickr


Why do bath bubbles pop when I sprinkle talcum powder on them?

croc attack!!! by Nizam Uddin, on FlickrFor most of us, kid’s birthday parties are a nightmare that are best avoided. Having to supervise one would be an experience with few perks. One of which would be getting to eat chocolate cake. Another would be getting to blow party bubbles. Because, let’s be honest, you never get too old for playing with bubbles.

Yet despite their instant fun factor, soap bubbles never last very long and pop disappointingly quickly. Up close, each bubble is a small, air-filled balloon with delicate walls made of a soap and water mix. With a surface thinner than a human hair, the bubble wall is so fragile that a tiny particle of dust can be enough to pierce it. Sprinkling talcum powder on bath bubbles, for example, is like showering a layer of balloons with pins.

But bath bubbles would never be there were it not for the soap – it is extremely difficult to make bubbles in pure water. Water has surface tension – a tendency to want to stay together in blobs and drops. Without soap, each time you make a plain water bubble, the water will pull itself together causing it to quickly collapse. With soapy water though, the soap molecules get in between the water molecules, reducing its surface tension, making bubble-making possible.

It is possible to get longer-lasting, sturdier bubbles by adding glycerine (also spelt ‘glycerin’). A sweet-tasting substance used for sore throats (you can buy it from supermarkets and pharmacies), glycerine has a special ability of slowing down how quickly water can evaporate. Free-floating bubbles eventually pop when the water in its wall evaporates, but glycerine molecules will form weak bonds with water molecules, ‘sticking’ them together and keeping the water inside a bubble’s wall inside for longer.

If you like, you could add glycerine to your bath water for an especially frothy and sweet cleanse. More cheerful and cleaner – hurray for longer lasting bubbles!

Answer by Dr Stu

Question sent from ‘JJ’

Image source: croc attack!!! by Nizam Uddin, on Flickr


Why do I crave stodge and snacks in the week before my period?

This was a star, and it is what I will do to your dreams... by ? |_ ?-\ ? Ø, on FlickrNature hasn’t been overly kind to women. Let’s look at childbirth. It is harder and more dangerous for humans than any other animal: the female pelvis is (usually) only just big enough to squeeze a baby’s big head through. And periods – or menstruation – are another particularly human curse. Most female animals don’t bleed at all. Then to further add insult to monthly injury, pre-menstrual food cravings scupper any well-meaning intentions to live a healthy life… Clearly someone upstairs wasn’t looking too kindly on Homo sapiens.

It is quite common for women to have cravings for certain food in the lead up to a period. Surveys show that these foods are usually high in carbohydrate (e.g. bread, muffins), high in fat (e.g. cheese) or both (doughnuts, buttered popcorn, chocolate). This desire to load up on calories is a consequence of changing hormone levels and starts soon after ovulation.

Ovulation usually happens at around the mid-point of a menstrual cycle – i.e. between two periods. It is when an ovary releases an egg into a fallopian tube. After this point, there is a gradual increase in the hormone progesterone in the blood – and this continues right up until the time of menstruation. Progesterone is designed to prepare a woman’s body for pregnancy by getting the womb (uterus) ready on the off chance that an egg comes into contact with a lucky sperm as it travels down the fallopian tube. But progesterone has other effects. One being that it makes the brain’s appetite-controlling regions go off kilter, prompting a longing to eat more. And as the progesterone increases in the run up to the period, these cravings get worse.

It’s unfortunate, but there is a logic behind progesterone’s effects. In getting the body ready for a possible pregnancy, progesterone serves to ensure the body is nourished enough so as to support a growing baby. Eating more is nature’s way of doing this.

Sadly, there is no simple solution to regular chocolate cravings. There are some reports of certain contraceptive pills helping some women – although the research is inconclusive. As a guy, all I can do is offer sympathy and support when the going is rough. And never ever make insensitive jokes or puns about pre-menstrual symptoms. Now that’s a solemn promise. Period.

Answer by Dr Stu

Image source: ? |_ ?-\ ? Ø, on Flickr


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