The mysterious Clovis culture, which appeared in North America about 13,000 years ago, appears to be the forerunner of Native Americans throughout the Americas, a study of DNA evidence suggests. Remains from an infant buried more than 12,000 years ago at a Clovis site in modern Montana held the genetic key.
Tagged with “dna” (7)
Maybe you thought your body was a noble castle poised against the onslaughts and invasions of the world. Well, think again. It turns out, we are the world. Our bodies are loaded with a jungle of microbial life, inside and out, that is essential to healthy life.
New science has found ten times as many bacteria cells as human cells in and on the human body. A load of microbes that work with us from the moment of birth in all kinds of key ways. Killing them off, avoiding them, may make us sick. Make us fat.
This hour, On Point: Microbes are us. The amazing full ecology of the human body.
IDEAS THAT ACCELERATE: SCIENCE MULTIPLIERS
The Dark Matter of Biology
Jonathan Eisen, Professor, University of California Davis
Compass Summit, a forum for true interaction and exchange, examines some of today’s most pressing problems through the lens of global citizenship, recognizing that human ingenuity is an unlimited resource. Guided by NPR’s Ira Flatow, an intimate group of some of the world’s best thinkers and doers convened along the rugged Palos Verdes coastline on Oct 23-26, 2011 at Terranea Resort to engage in meaningful conversation, ask questions, and challenge ideas — we invite you to join in the conversation.
Jonathan Eisen is a Professor at the University of California, Davis. His research focuses on the evolution of new functions and the genomic diversity of microbes and microbial communities. Eisen is also a vocal advocate for “open science”, the Academic Editor-in-Chief of PLoS Biology, an active and award-winning blogger (e.g., http://phylogenomics.blogspot.com), and a scientific prankster.
Scientist and entrepreneur Craig Venter made headlines in 2000 when he was one of the first to sequence the human genome.
Now, he’s announced another big step: the creation of synthetic life in a laboratory – a bacterium with a cooked-up, man-made genetic code.
The breakthrough could eventually lead to tailor-made organisms and big benefits in medicine, energy and beyond.
But what about the ethics – and the risks – of making life in a lab?
Richard Dawkins’ The God Delusion created a storm of controversy over the question of God’s existence. Now, in The Greatest Show on Earth, Dawkins presents a stunning counterattack against advocates of "Intelligent Design" that explains the evidence for evolution while keeping an eye trained on the absurdities of the creationist argument.
More than an argument of his own, it’s a thrilling tour into our distant past and into the interstices of life on earth. Taking us through the case for evolution step-by-step, Dawkins looks at DNA, selective breeding, anatomical similarities, molecular family trees, geography, time, fossils, vestiges and imperfections, human evolution, and the formula for a strong scientific theory.
Dawkins’ trademark wit and ferocity is joined by an infectious passion for the beauty and strangeness of the natural world, proving along the way that the mechanisms of the natural world are more miraculous — a "greater show" — than any creation story generated by any religion on earth.
“Everything in our cells is either made by the ribosome, or made by another molecule that itself was made by the ribosome” says Professor Venki Ramakrishnan, one of the handful of experts to unpick the secrets of this powerhouse of life.
And as well as being a universal fabricator – shared in essence by every living thing – the ribosome could be the most direct connection within us to the very origins of life, that warm pond of chemicals 4 billion years ago, where self-replicating molecules, perhaps made of RNA like the heart of the ribosome, started the long ascent to complexity.
To really read DNA accurately and understand it thoroughly, you need to be able to write it from scratch and make it live, Venter explained.
His sequencing the first diploid human genome (with the genes from both parents) last year showed there is much more genetic variation between humans than first thought. His current goal is to fully sequence 10,000 humans and bring the price for each sequence down to $1,000. With that data, his says, “We’ll begin to really learn what’s nature and what’s nurture.”
“Microbes make up one half of the Earth’s biomass.” Venter’s shotgun sequencing of open-ocean microbial samples revealed that every milliliter of ocean has one million bacteria and archaea and ten million viruses even in supposedly barren waters. Taking samples on a round-the-world sailing trip showed that every 200 miles the genes in the microbes are 85% different.
“Microbes dominate evolutionary diversity,” Venter said. Some 50,000 major gene familes have been discovered. Humans and other complex animals have a small fraction of that in our own genes, but the “microbiome” of our onboard microbes carry the full richness. Only 1/10th of the cells in a human are human; the rest are microbes. There are 1,000 species in our mouths, another 1,000 in our guts, another 500 on our skins, and those with vaginas have yet another 500 species.