Power, Sex, Suicide: Mitochondria and the Meaning of Life [EPUB]
21 September 2014, 11:12
2006 | EPUB + MOBI | 0.9/1.48MB
If it weren't for mitochondria, scientists argue, we'd all still be single-celled bacteria. Indeed, these tiny structures inside our cells are important beyond imagining. Without mitochondria, we would have no cell suicide, no sculpting of embryonic shape, no sexes, no menopause, no aging.
In this fascinating and thought-provoking book, Nick Lane brings together the latest research in this exciting field to show how our growing insight into mitochondria has shed light on how complex life evolved, why sex arose (why don't we just bud?), and why we age and die. These findings are of fundamental importance, both in understanding life on Earth, but also in controlling our own illnesses, and delaying our degeneration and death. Readers learn that two billion years ago, mitochondria were probably bacteria living independent lives and that their capture within larger cells was a turning point in the evolution of life, enabling the development of complex organisms. Lane describes how mitochondria have their own DNA and that its genes mutate much faster than those in the nucleus. This high mutation rate lies behind our aging and certain congenital diseases. The latest research suggests that mitochondria play a key role in degenerative diseases such as cancer. We also discover that mitochondrial DNA is passed down almost exclusively via the female line. That's why it has been used by some researchers to trace human ancestry daughter-to-mother, to "Mitochondrial Eve," giving us vital information about our evolutionary history.
Written by Nick Lane, a rising star in popular science, Power, Sex, Suicide is the first book for general readers on the nature and function of these tiny, yet fascinating structures.
40 Years of Evolution [EPUB]
21 September 2014, 08:27
2014 | EPUB + AZW3 | 6.2/6.94MB
Renowned evolutionary biologists Peter and Rosemary Grant have produced landmark studies of the Galápagos finches first made famous by Charles Darwin. In How and Why Species Multiply, they offered a complete evolutionary history of Darwin's finches since their origin almost three million years ago. Now, in their richly illustrated new book, 40 Years of Evolution, the authors turn their attention to events taking place on a contemporary scale. By continuously tracking finch populations over a period of four decades, they uncover the causes and consequences of significant events leading to evolutionary changes in species.
The authors used a vast and unparalleled range of ecological, behavioral, and genetic data--including song recordings, DNA analyses, and feeding and breeding behavior--to measure changes in finch populations on the small island of Daphne Major in the Galápagos archipelago. They find that natural selection happens repeatedly, that finches hybridize and exchange genes rarely, and that they compete for scarce food in times of drought, with the remarkable result that the finch populations today differ significantly in average beak size and shape from those of forty years ago. The authors' most spectacular discovery is the initiation and establishment of a new lineage that now behaves as a new species, differing from others in size, song, and other characteristics. The authors emphasize the immeasurable value of continuous long-term studies of natural populations and of critical opportunities for detecting and understanding rare but significant events.
By following the fates of finches for several generations, 40 Years of Evolution offers unparalleled insights into ecological and evolutionary changes in natural environments.
First Contact: Scientific Breakthroughs in the Hunt for Life Beyond Earth [EPUB]
13 September 2014, 22:57
2011 | EPUB | 3.43MB
Are we alone in the universe? Almost certainly not.
In First Contact, Marc Kaufman provides a gripping tour of the magnificent new science of astrobiology that is closing in on the discovery of extraterrestrial life. In recent decades, scientists generally held that the genesis of life was unique to Earth: It was too delicate a process, and the conditions needed to support it too fragile, for it to exist anywhere else. But we are now on the verge of the biggest discovery since Copernicus and Galileo told us that Earth is not at the center of the universe. New scientific breakthroughs have revolutionized our assumptions about the building blocks of life and where it may be found. Scientists have hunted down and identified exoplanets, those mysterious balls in the universe that orbit distant suns not too different from our own. They have discovered extremophiles, the extraordinary microbes that thrive in environments of intense heat or cold that may mimic the inhospitable conditions of other planets. They have landed rovers on Mars and detected its methane, a possible signature of past life. And they have created sophisticated equipment to sweep the sky for distant radio signals and to explore the deep icebound lakes of Antarctica. Each of these developments has brought forth a new generation of out-of-the-box researchers, adventurers, and thinkers who are each part Carl Sagan, part Indiana Jones, part Watson and Crick—and part forensic specialists on CSI: Mars.
In this masterful book, Kaufman takes us to the frontiers of astrobiology’s quest for extraterrestrial life and shows how this quest is inextricably linked with the quest to understand life on Earth. He takes us deep under the glaciers of Antarctica, into the mouth of an Alaskan volcano, and beneath the Earth into the unbearable heat of a South African mine, and leads us to the world’s driest desert. For thousands of years, humans have wondered about who and what might be living beyond the confines of our planet. First Contact transports us into the cosmos to bring those musings back to Earth and recast our humanity.