InnerNature: Sex — The key to diversity

By Vidya Rajan, Columnist, The Times In his book “Evolution: The Triumph of an Idea,” Carl Zimmer concedes: “Sex is not only unnecessary, but it ought to be a recipe for evolutionary disaster. For one thing, it is an inefficient way to reproduce…And sex carries other costs as well…By all rights, any group of animals that evolves sexual reproduction should be promptly outcompeted by nonsexual...

Inner Nature: Immunity — Autosurveillance

By Vidya Rajan, Columnist, The Times The immune system is the mechanism that protects and defends the body. Although its main purpose is defense against attack, the immune system is also a barrier, border patrol, soldier, police, doctor, parent, and amazingly, a fortune-teller, all in one package. Not only that, it exists in every living organism from bacteria to plants to animals to protect against...

Inner Nature: Digestion and food processing

By Vidja Rajan, Columnist, The Times The previous group of Inner Nature articles were loosely organized around how organisms sense the external environment using vision, sound, touch, taste and smell. What is most remarkable about this cluster of what appears to be completely different mechanisms is the profound underlying similarity. This similarity is due to the outcome of notionally different...

Inner Nature: Metamorphosis – Buggy Development

By Vidya Rajan, Columnist, The Times The growth of a single cell from a fertilized egg, or zygote, to an adult composed of trillions of cells is amazing and magical. This process which scientists, with their knack for understatement, call “development” happens with most eukaryotic organisms – those that have cells with a nucleus and other membranous compartments. Nucleated eukaryotic cells...