People like to think of objects as themselves having purpose and intent, irrelevant of context. Another view is that context itself defines the object.
When we look at genes, people seem to be looking for singular, simple mechanisms to suggest a single actor in every situation — the purpose or intent to objects discussed above. More likely, multiple mechanisms exist at any one time, and together a context, these provide a force of evolution.
Researchers led by Evan Eichler, a Howard Hughes Medical Institute investigator at the University of Washington in Seattle, compared the genomes of macaques, orangutans, gorillas, chimpanzees, bonobos and humans. The scientists found that chunks of the genomes had been copied and rearranged, sometimes multiple times, within each of the lineages.
After orangutans branched off the primate family tree, duplication rates accelerated dramatically in the common ancestor of gorillas, chimpanzees and humans.The burst continued in the common ancestor of humans and chimps, but then slowed again. At the same time that duplication rates were heating up, other types of mutation â€” such as single letters changes in the genetic sequence â€” slowed down.
All the duplication activity resulted in structural differences in the architecture of the genome among the species on a scale not previously appreciated. Because earlier studies had only looked at single genes or small parts of the genome, these larger-scale changes were not apparent.
â€œThis paper suggests that the real variation leading to the human lineage is structural,â€ says Mark Gerstein, a bioinformatician at Yale University. â€œI think itâ€™s plausible that copy number or structural variation can affect things even more than mutation â€“ single base changes â€“ can.â€
Our previous DNA comparison was like looking at the computer code for a word processor and a video game and saying, “Hey, these are similar! They both use this ‘printf’ statement!”
Our new comparison is looking at the structures — like a for-next loop advancing by fours and escaping odd numbers — and the types of data the application handles. In this, we can see the word processor as a manipulator of text data, and video games, of rapidly-changing graphical content.
Similarly, we learned that lateral transfer occurs instead of purely linear transfer:
The idea of a tree came under scrutiny. A web of life that allows for lateral gene transfer was instead proposed.
Though staunch supporters of the tree of life dismissed this observation as some kind of an aberration, the result of a study published last year in the Proceedings of the National Academy of Sciences showed that 80 per cent of bacteria and archaea showed lateral gene transfer.
Evolutionary biologists had the axe ready to cut down the tree of life further. They showed that lateral gene transfer was seen in eukaryotes as well. Eukaryotes â€” amoeba and algae â€” are themselves a product of fusion of bacteria and archaea.
And there are other taboos we shatter — or re-shatter:
The idea that a person’s character can be glimpsed in their face dates back to the ancient Greeks. It was most famously popularised in the late 18th century by the Swiss poet Johann Lavater, whose ideas became a talking point in intellectual circles. In Darwin’s day, they were more or less taken as given. It was only after the subject became associated with phrenology, which fell into disrepute in the late 19th century, that physiognomy was written off as pseudoscience.
Researchers around the world are re-evaluating what we see in a face, investigating whether it can give us a glimpse of someone’s personality or even help to shape their destiny. What is emerging is a “new physiognomy” which is more subtle but no less fascinating than its old incarnation.
More recently, researchers have re-examined the link between appearance and personality, notably Anthony Little of the University of Stirling and David Perrett of the University of St Andrews, both in the UK. They pointed out that the Michigan studies were not tightly controlled for confounding factors: the participants could have been swayed by posture, movement, clothing and so on. But when Little and Perrett re-ran the experiment using mugshots rather than live subjects, they also found a link between facial appearance and personality – though only for extroversion and conscientiousness (Social Cognition, vol 24, p 607).
What they’re going to realize is that grouped traits reflect structures.
We shouldn’t be looking for single genes — but groups of genes, that like different printf and for-next statements, define the structures in the computer code of our genes.
Appearance will reflect genetics which will reflect abilities, and any trait will come grouped with others.
This will, of course, be highly controversial.