Scienec: Technoquest

Q: What is the smallest spider in the world?

The smallest spider is the Mygalomorph spider from Borneo, whose body measures just 0.5mm long - the size of a coffee granule. The largest is the goliath bird-eating spider, the largest of which has a leg span of 29cm (11in) - the length of your forearm.

Q: How long do spiders live?

Ordinary spiders live for about a year, although up to five to six months of this may be spent in the egg stage. However, some South American tarantulas can live for as long as 20 years, while some tropical jumping spiders only live for three months.

Q: How is snake venom produced?

Venom is produced at the back of the snake's head (behind the eyes). Glands similar to those that produce our saliva make and store a cocktail of venoms, toxins and enzymes, which travel through ducts to either fangs or groves in the teeth. The venoms work in different ways: they can paralyse prey (cobra venom affects the nervous system) or digest tissues and organs (rattle snakes) which helps them in their food intake.

Q: Is there such a thing as a bionic eye?

People may be either blind from birth or have lost their sight through disease or an accident. For those born blind, an artificial eye may not be all that useful as their visual cortex has not been trained to see. For those that have lost their vision later on in life, a bionic eye (an implant that replaces damaged retinal cells) may restore some of their sight.

Retinal implants are constructed from 25 electrodes just a thousandth of a millimetre thick, and incorporate a miniature solar panel. When the panels absorb light, tiny currents are generated in the implants which then stimulate the ganglion cells beneath, bypassing damaged retinal cells.

So far, the implants have worked in animals and in one human volunteer who had gone blind through glaucoma. The patient could see a light shone in the eye, and make out simple letters. If more electrodes are used, the wearer's vision might be even better. Next, the researchers will need to make an implant that does not corrode in the salty solutions of the eye, and will not slice into the retina (the implants are razor sharp as they are so thin). Researchers remain hopeful that eventually such implants may restore sight to some blind people.

Q: Why do your eyebrows grow as you get older?

The continued growth of hair in men is thought to be due to the male sex hormones (androgens). Hair in different parts of the body varies in its sensitivity to androgens and eyebrows, nose, ear and patches on the top of the shoulder respond to continual high levels of the hormones. It therefore does not usually appear in women, who have much lower levels of androgens. Why evolution should have produced them is unclear. There is, however, a hint from some species that females seek out males who are older because that shows they are good at surviving and so must have a fit set of genes. The males of these species develop outward signs of their age. Perhaps going grey and sprouting ear and nose hairs was once attractive to women and so men showing them were successful at getting their genes into the next generation.

You can also visit the technoquest World Wide Web site at http://www.sciencenet.org.uk

Suggested Topics
Arts and Entertainment
Smart mover: Peter Bazalgette

film
Arts and Entertainment
'Old Fashioned' will be a different kind of love story to '50 Shades'
film
Arts and Entertainment
Tracey Emin's 'My Bed' is returning to the Tate more than 15 years after it first caused shockwaves at the gallery
artTracey Emin's bed returns to the Tate after record sale
Arts and Entertainment

film
Arts and Entertainment
The Great British Bake Off contestants line-up behind Sue and Mel in the Bake Off tent

TV
PROMOTED VIDEO
Have you tried new the Independent Digital Edition apps?
Arts and Entertainment
Beast would strip to his underpants and take to the stage with a slogan scrawled on his bare chest whilst fans shouted “you fat bastard” at him

music
Arts and Entertainment
On set of the Secret Cinema's Back to the Future event

film
Arts and Entertainment
Gal Gadot as Wonder Woman

film
Arts and Entertainment
Pedro Pascal gives a weird look at the camera in the blooper reel

TV
Arts and Entertainment
Public vote: Art Everywhere poster in a bus shelter featuring John Hoyland
art
Arts and Entertainment
Peter Griffin holds forth in The Simpsons Family Guy crossover episode

TV
Arts and Entertainment
Judd Apatow’s make-it-up-as-you-go-along approach is ideal for comedies about stoners and slackers slouching towards adulthood
filmWith comedy film audiences shrinking, it’s time to move on
Arts and Entertainment
booksForget the Man Booker longlist, Literary Editor Katy Guest offers her alternative picks
Arts and Entertainment
Off set: Bab El Hara
tvTV series are being filmed outside the country, but the influence of the regime is still being felt
Arts and Entertainment
Red Bastard: Where self-realisation is delivered through monstrous clowning and audience interaction
comedy
Arts and Entertainment
O'Shaughnessy pictured at the Unicorn Theatre in London
tvFiona O'Shaughnessy explains where she ends and her strange and wonderful character begins
Arts and Entertainment
The new characters were announced yesterday at San Diego Comic Con

TV
Arts and Entertainment
Rhino Doodle by Jim Carter (Downton Abbey)

TV
Arts and Entertainment
No Devotion's Geoff Rickly and Stuart Richardson
musicReview: No Devotion, O2 Academy Islington, London
Arts and Entertainment
Christian Grey cradles Ana in the Fifty Shades of Grey film

film
Arts and Entertainment
Comedian 'Weird Al' Yankovic

Is the comedy album making a comeback?

comedy
Arts and Entertainment
While many films were released, few managed to match the success of James Bond blockbuster 'Skyfall'
film
Arts and Entertainment
Jamie Dornan as Christian Grey in the first-look Fifty Shades of Grey movie still

film
Arts and Entertainment
Sue Perkins and Mel Giedroyc, centre, are up for Best Female TV Comic for their presenting quips on The Great British Bake Off

TV
Arts and Entertainment
Martin Freeman as Lester Nygaard in the TV adaptation of 'Fargo'

TV
Independent
Travel Shop
the manor
Up to 70% off luxury travel
on city breaks Find out more
santorini
Up to 70% off luxury travel
on chic beach resorts Find out more
sardina foodie
Up to 70% off luxury travel
on country retreats Find out more
Latest stories from i100
Have you tried new the Independent Digital Edition apps?

ES Rentals

    Independent Dating
    and  

    By clicking 'Search' you
    are agreeing to our
    Terms of Use.

    Save the tiger: The animals bred for bones on China’s tiger farms

    The animals bred for bones on China’s tiger farms

    The big cats kept in captivity to perform for paying audiences and then, when dead, their bodies used to fortify wine
    A former custard factory, a Midlands bog and a Leeds cemetery all included in top 50 hidden spots in the UK

    A former custard factory, a Midlands bog and a Leeds cemetery

    Introducing the top 50 hidden spots in Britain
    Ebola epidemic: Plagued by fear

    Ebola epidemic: Plagued by fear

    How a disease that has claimed fewer than 2,000 victims in its history has earned a place in the darkest corner of the public's imagination
    Chris Pratt: From 'Parks and Recreation' to 'Guardians of the Galaxy'

    From 'Parks and Recreation' to 'Guardians of the Galaxy'

    He was homeless in Hawaii when he got his big break. Now the comic actor Chris Pratt is Hollywood's new favourite action star
    How live cinema screenings can boost arts audiences

    How live cinema screenings can boost arts audiences

    Broadcasting plays and exhibitions to cinemas is a sure-fire box office smash
    Shipping container hotels: Pop-up hotels filling a niche

    Pop-up hotels filling a niche

    Spending the night in a shipping container doesn't sound appealing, but these mobile crash pads are popping up at the summer's biggest events
    Native American headdresses are not fashion accessories

    Feather dust-up

    A Canadian festival has banned Native American headwear. Haven't we been here before?
    Boris Johnson's war on diesel

    Boris Johnson's war on diesel

    11m cars here run on diesel. It's seen as a greener alternative to unleaded petrol. So why is London's mayor on a crusade against the black pump?
    5 best waterproof cameras

    Splash and flash: 5 best waterproof cameras

    Don't let water stop you taking snaps with one of these machines that will take you from the sand to meters deep
    Louis van Gaal interview: Manchester United manager discusses tactics and rebuilding after the David Moyes era

    Louis van Gaal interview

    Manchester United manager discusses tactics and rebuilding after the David Moyes era
    Will Gore: The goodwill shown by fans towards Alastair Cook will evaporate rapidly if India win the series

    Will Gore: Outside Edge

    The goodwill shown by fans towards Alastair Cook will evaporate rapidly if India win the series
    The children were playing in the street with toy guns. The air strikes were tragically real

    The air strikes were tragically real

    The children were playing in the street with toy guns
    Boozy, ignorant, intolerant, but very polite – The British, as others see us

    Britain as others see us

    Boozy, ignorant, intolerant, but very polite
    How did our legends really begin?

    How did our legends really begin?

    Applying the theory of evolution to the world's many mythologies
    Watch out: Lambrusco is back on the menu

    Lambrusco is back on the menu

    Naff Seventies corner-shop staple is this year's Aperol Spritz