LUCA (Last Universal Common Ancestor) - 2

.....contd 2.

To zero in on exactly when LUCA appeared on Earth, scientists had to work backward. First, the team compared genes in living species and counted the mutations that have occurred since sharing a common ancestor with LUCA. Using a genetic equation based on the time of separation between species, the team worked out that LUCA must have been mucking around on Earth as nearly as 400 million years after its creation, which puts this organism smack in the middle of the hellish geologic nightmare known as the Hadean Eon.

"The evolution history of genes is complicated by their exchange between lineages", University of Bristol's Edmund Moody, the lead author of the study, said in a press statement, "We have to use complex evolutionary models to reconcile the evolutionary history of genes with the genealogy of species".

Not satisfied with just learning its age, the team took things a step further and retraced the physiological characteristics of living species to understand what LUCA must have been like 4.2 billion years ago and the results gave some surprising answers. The scientists estimate that while LUCA was a simple prokaryote, it likely had an immune system, meaning it was already fighting off primordial viruses.

"It's clear that LUCA was exploiting and changing its environment but it is unlikely to have lived alone", University of Exeter's Tim Lenton, a co-author of the study, said in a press statement. "Its waste would have been food for other microbes, like methanogens that would have helped to create a recycling ecosystem".

While LUCA is the oldest common ancestor we know of, scientists still don't understand how life evolved from its very origins to the early communities of which LUCA is a part. Further studies will need to dive deeper into this primordial history and uncover exactly how, you, me and every other living thing, came to be.

Courtesy. Darren Orf

Tailpiece.

Got up a trifle past 6, the chores and was ready by a half past 8.

Met Suresh Gopi at his residence and decided on the way forward to have our Maasaacharanam conclusion program at New Delhi during the first week of August and the release of Muthachchan's biography, in English. Met Sreekkuttan also there.

To KIMS and met Dr Jithu, the Surgical Specialist, who had reviewed Maman's wound on his eyebrow. It's healing well. A new dressing was put on the wound.

At the Holy Angel's Convent to see tomorrow's venues for the public meeting and the state level quiz competition.

Lunch was rice, curd and and 'natholi' fried.

The evening's lecture at Poojappura was "Grandhasala Prasthaanavum Saamoohika Navodhaanavum" by Venpakal Ganesan.

Met Shajahan, the proprietor of the Kunnil Department Store. A nice, unassuming guy!

Dinner consisted of dosas and chutney.