The question of how life first emerged here on Earth is a mystery that continues to elude scientists. Despite everything that scientists have learned from the fossil record and geological history, it is still not known how organic life emerged from inorganic elements (a process known as abiogenesis) billions of years ago.
Modern medicine’s ability to keep us alive makes it tempting to think human evolution may have stopped. Better healthcare disrupts a key driving force of evolution by keeping some people alive longer, making them more likely to pass on their genes. But if we look at the rate of our DNA’s evolution, we can see that human evolution hasn’t stopped – it may even be happening faster than before.
Almost all life on earth is based on DNA being copied, or replicated, and understanding how this process works could lead to a wide range of discoveries in biology and medicine. Now for the first time scientists have been able to watch individual steps in the replication of a single DNA molecule, with some surprising findings. For one thing, there’s a lot more randomness at work than has been thought.
Until recently, anthropologists drew the human family tree in the same way that my 10-year-old son solves a maze. He finds it much easier to work from the end to the beginning, because blind alleys lead with depressing sameness away from the start. In just this way, scientists once traced our own lineage from the present into the past, moving backward through a thicket of fossil relatives, each perched upon its own special branch to extinction.
DNA sequencing technology is helping scientists unravel questions that humans have been asking about animals for centuries. By mapping out animal genomes, we now have a better idea of how the giraffe got its huge neck and why snakes are so long. Genome sequencing allows us to compare and contrast the DNA of different animals and work out how they evolved in their own unique ways
The brain may not only control our thoughts and basic physical functions. Recent studies indicate that it also controls the way our body responds to the threat of bacterial infections. It does this by boosting the production of a protective molecule called PCTR1 that helps white blood cells kill the invading bacteria.
A baby boy, the first child to be born using a new technique that incorporates DNA from three people, is now five months old. It is great news – the birth of a healthy baby conceived by this new procedure is a major step forward and will lead to a new way of preventing the inheritance of mitochondrial diseases.