Questions and answers provided by Science Line's Dial-a-Scientist on 0345 600444
Monday 02 December 1996
A Fossils of mammal-like reptiles which were around before the dinosaurs show that their teeth were differentiated like today's mammals. Today's reptiles have teeth that are all the same pointed shape. But the early mammal-like reptiles had teeth designed for different purposes - canines and incisors for ripping food apart, molars for grinding it.
Q Why do babies often wake up at night?
A Our sleeping patterns change during our lives. Babies sleep for about 16 hours in 24 while two-year-olds only sleep for nine to 12 hours. Older people can manage with only four to six hours a night. Babies also spend up to 50 per cent of their sleep in a REM state while adults spend only 25 per cent. Babies sleep in short bursts, maximising their chances of feeding by spreading their 16 hours of sleep throughout a 24-hour period. So even if kept awake all day, a baby is unlikely to sleep through the night because it's programmed not to.
Q Do birds get earwax?
A Birds do not have an outer ear and so wax is unlikely to form.
Q Why do we have freckles on the backs of our hands but none on our fingers?
A Freckles are clumps of skin cells with more melanin in them than other cells. Freckles tend to form when our skin is exposed to sunshine. As we walk we tend to hold our hands with our fingers curled inwards, shading them from the sunlight and so reducing the chance of freckles forming.
You can also visit the technoquest World Wide Web site at http://www.campus.bt.com/CampusWorld/pub/ScienceNet
Questions for this column can be submitted by e-mail to email@example.com
food + drinkMichelin-starred Tom Sellers on being this year's hottest property
tvParents (and kids) rejoice! A new wave of fantastic family entertainment is here
booksGeese, gorillas, grandads... and growing up
food + drinkHow one grocery e-tailer is gearing up for the Yuletide rush
food + drink
travelFor broadcaster Mishal Husain, a long-haul Club Med holiday was a chance for her family to explore its sense of 'zen' and 'animation'
Nelson Mandela: 11 inspirational quotes to live your life by
Queen to miss Nelson Mandela funeral over security and long-haul flight concerns
'Never a good time to increase MPs' pay': Jack Straw defends politicians' 11% pay rise in face of public outrage
The 'terrorist' and the Tories: What did Nelson Mandela really think of Margaret Thatcher?
Japan cracks down on leaks after scandal of Fukushima nuclear power plant
- 1 Hundreds arrested as Canadian police smash worldwide paedophile ring
- 2 Sherlock series 3: Benedict Cumberbatch and Martin Freeman provide teasers for the biggest comeback in British television
- 3 The man who made Femen: New film outs Victor Svyatski as the mastermind behind the protest group and its breast-baring stunts
- 4 Mass murder in the Middle East is funded by our friends the Saudis
- 5 Japan cracks down on leaks after scandal of Fukushima nuclear power plant
- < Previous
- Next >
£80000 - £100000 per annum + Benefits + Bonus: Harrington Starr: Senior C++ De...
£25000 - £50000 per annum + Benefits + Bonus: Harrington Starr: C++ Server Dev...
£300 - £350 per day: Harrington Starr: Leading Electronic Trading Software Ven...
£23999 - £32001 per annum + Benefits: Pro-Recruitment Group: An independent ac...