Power, Sex, Suicide: Mitochondria and the Meaning of Life

Power, Sex, Suicide: Mitochondria and the Meaning of Life

Power, Sex, Suicide: Mitochondria and the Meaning of Life

Power, Sex, Suicide: Mitochondria and the Meaning of Life

Synopsis

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, Suicideis the first book for general readers on the nature and function of these tiny, yet fascinating structures.

Excerpt

The void between bacterial and eukaryotic cells is greater than any other in biology. Even if we begrudgingly accept bacterial colonies as true multicellular organisms, they never got beyond a very basic level of organization. This is hardly for lack of time or opportunity—bacteria dominated the world for two billion years, have colonized all thinkable environments and more than a few unthinkable ones, and in terms of biomass still outweigh all multicellular life put together. Yet for some reason, bacteria never evolved into the kind of multicellular organism that a man on the street might recognize. In contrast, the eukaryotic cell appeared much later (according to the mainstream view) and in the space of just a few hundred million years—a fraction of the time available to bacteria—gave rise to the great fountain of life we see all around us.

The Nobel laureate Christian de Duve has long been interested in the origin and history of life. He suggests in a wise final testament, Life Evolving, that the origin of the eukaryotes may have been a bottleneck rather than an improbable event—in other words, their evolution was an almost inevitable consequence of a relatively sudden change in the environmental conditions, such as a rise in the amount of oxygen in the atmosphere and oceans. Of all the populations of proto-eukaryotes living at the time, one form simply happened to be better adapted and expanded rapidly through the bottleneck to take advantage of the changing circumstances: it prospered, while less well-adapted competing forms died out, giving a misleading impression of chance. This possibility depends on the actual sequence of events and selection pressures involved, and can't be ruled out until these are known with certainty. And of course, when we are talking of selection pressures exerted two billion years ago, it is unlikely that we can ever be certain; nonetheless, as I mentioned in the Introduction, it is possible to exclude some of the possibilities by considering modern molecular biology, and to narrow down a list of the most likely possibilities.

Despite my enormous respect for de Duve, I don't find his bottleneck thesis very convincing. It is too monolithic, and the sheer variety of life weighs against it—there seems to be a place for almost everything. The whole world did not change at once, and many varied niche environments persisted. Perhaps most . . .

Search by... Author
Show... All Results Primary Sources Peer-reviewed

Oops!

An unknown error has occurred. Please click the button below to reload the page. If the problem persists, please try again in a little while.