Over at one of my favorite science /tech sites -
Arstechnica - John Timmer has a
good write up about 5 essential aspects of evolution that you should know:
- A really inefficient solution can be a lot better than the alternative
- Evolution solves problems in parallel
- Evolution doesn't happen overnight
- A million years is a lot longer than we think it is
- We wouldn't recognize a key transition while it was happening
Useful to keep these in mind when explaining and /or arguing about how evolution works.
Dear Dr.Kher,
ReplyDeleteCan you or someone else translate this Nature article to something everyone can understand (not just biologists!)?
Thanks!!
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Reconstructing Indian population history
David Reich1,2*, Kumarasamy Thangaraj3*, Nick Patterson2*, Alkes L. Price2,4* & Lalji Singh3
India has been underrepresented in genome-wide surveys of human variation. We analyse 25 diverse groups in India to provide strong evidence for two ancient populations, genetically divergent, that are ancestral to most Indians today. One, the ‘Ancestral North Indians’ (ANI), is genetically close to Middle Easterners, Central Asians, and Europeans, whereas the other, the ‘Ancestral South Indians’ (ASI), is as distinct from ANI and East Asians as they are from each other. By introducing
methods that can estimate ancestry without accurate ancestral populations, we show that ANI ancestry ranges from 39–71%
in most Indian groups, and is higher in traditionally upper caste and Indo-European speakers. Groups with only ASI ancestry may no longer exist in mainland India. However, the indigenous Andaman Islanders are unique in being ASI-related groups without ANI ancestry. Allele frequency differences between groups in India are larger than in Europe, reflecting strong founder effects whose signatures have been maintained for thousands of years owing to endogamy. We therefore predict that there will be an excess of recessive diseases in India, which should be possible to screen and map genetically.
http://www.nature.com/nature/journal/v461/n7263/pdf/nature08365.pdf