Programmed life

Written by Khalil A. Cassimally

Does aging happen by chance? Is agingrepparttar breaking down of an organism tillrepparttar 105814 latter eventually stops working?

According to Valter Longo’s latest research, which was published inrepparttar 105815 September 27 edition ofrepparttar 105816 Journal of Cell Biology, aging is a programmed process. For Longo’s part, aging is supposed to ensurerepparttar 105817 premature death ofrepparttar 105818 majority of a population.

The dead will then consequently provide nutrients forrepparttar 105819 sake of a few individuals who have acquired genetic mutations. (Think of yeast rather than big complex mammals.) These mutants are more adapted to their environment thanrepparttar 105820 other ‘normal’ organisms. Therefore these ‘sacrificial’ deaths increaserepparttar 105821 chances of reproduction ofrepparttar 105822 mutants asrepparttar 105823 latter will have more nutrients to feed on.

Now Charles Darwin may not be very happy with Longo’s theory. Darwin’s natural selection happens at individual level. The better suited to its environment an organism is,repparttar 105824 more probable that it will reproduce. This ensures thatrepparttar 105825 species changes or evolves over time as such type of reproduction brings genetic changes torepparttar 105826 offsprings. This makesrepparttar 105827 offsprings more adapted to their ever-changing environment.

Longo’s theory however rests onrepparttar 105828 group selection theory. Many scientists think that this theory is incorrect. The latter proposes that selection happens not at individual level but at group level instead.

Mosquitoes like my blood

Written by Khalil A. Cassimally

Here in Mauritius, mosquitoes are in paradise. The male mosquitoes have allrepparttar fruits they’ll ever dream of – god knows whether they actually dream – all year long whilerepparttar 105813 female mosquitoes can choose from a numerous number of tourists to feed on.

It is of no surprise that tourists get bitten more than we, locals do. Andrepparttar 105814 reaction which occurs onrepparttar 105815 tourists’ skin is quiet unusual to me. A large red swelling develops. It is about twicerepparttar 105816 size thatrepparttar 105817 one which would have formed on my skin if I was to get bitten. Apparentlyrepparttar 105818 bite that a tourist receives is also more irritant. In my opinion, this is because foreigners are not as used to get mosquito bites than Mauritians do. But one thing is for sire though: some people do get bitten more than others.

Why is this so? Or rather, why are some people bitten less? James Logan, a research student atrepparttar 105819 Biotechnology and Biological Sciences Research Council (BBSRC) has found that some people give off ‘masking’ odours that prevent

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