6 Quotes Tagged: Biology

Those who are not afraid of monsters tend not to leave descendants.

The secrets of evolution are death and time — the deaths of enormous numbers of lifeforms that were imperfectly adapted to the environment; and time for a long succession of small mutations.

"Bumblebees detect the polarization of sunlight, invisible to uninstrumented humans; put vipers sense infrared radiation and detect temperature differences of 0.01C at a distance of half a meter; many insects can see ultraviolet light; some African freshwater fish generate a static electric field around themselves and sense intruders by slight perturbations induced in the field; dogs, sharks, and cicadas detect sounds wholly inaudible to humans; ordinary scorpions have micro — seismometers on their legs so they can detect in darkness the footsteps of a small insect a meter away; water scorpions sense their depth by measuring the hydrostatic pressure; a nubile female silkworm moth releases ten billionths of a gram of sex attractant per second, and draws to her every male for miles around; dolphins, whales, and bats use a kind of sonar for precision echo-location.
The direction, range, and amplitude of sounds reflected by to echo-locating bats are systematically mapped onto adjacent areas of the bat brain. How does the bat perceive its echo-world? Carp and catfish have taste buds distributed over most of their bodies, as well as in their mouths; the nerves from all these sensors converge on massive sensory processing lobes in the brain, lobes unknown in other animals. how does a catfish view the world? What does it feel like to be inside its brain? There are reported cases in which a dog wags its tail and greets with joy a man it has never met before; he turns out to be the long-lost identical twin of the dog's "master", recognizable by his odor. What is the smell-world of a dog like? Magnetotactic bacteria contain within them tiny crystals of magnetite - an iron mineral known to early sailing ship navigators as lodenstone. The bacteria literally have internal compasses that align them along the Earth's magnetic field. The great churning dynamo of molten iron in the Earth's core - as far as we know, entirely unknown to uninstrumented humans - is a guiding reality for

The same few dozen organic molecules are used over and over again in biology for the widest variety of functions.

Individual asexual organisms die by mistake - when the run out of something, or when they experience a lethal accident. Sexual organisms are designed to die, preprogrammed to do so. Death serves as a poignant reminder of our limitations and frailties - and of the bond with our ancestors who, in a way, died that we might live.

Still, the alien biologist might be excused for lumping together the whole biosphere - all the retroviruses, mantas, foraminifera, mongongo trees, tetanus bacilli, hydras, diatoms, stromatolite-builders, sea slugs, flatworms, gazelles lichens, corals, spirochetes, banyans, cave ticks, least bitters, caracaras, tufted puffins, ragweed pollen, wold spiders, horseshoe crabs, black mambas, monarch butterflies, whiptail lizards, trypanosomes, birds of paradise, electric eels, wild parsnips, arctic terns, fireflies, titis, chrysanthemums, hammerhead sharks, rotifers, wallabies, malarial plasmodia, tapirs, aphids, water moccasins, morning glories, whooping cranes, komodo dragons, periwinkles millipede larvae, angler fish, jellyfish lungfish, yeast, giant redwoods, tardigrades, archaebacteria, sea lilies, lilies of the valley, humans bonobos, squid and humpback whales - as, simply, Earthlife. The arcane distinctions among these swarming variations on a common theme may be left to specialists or graduate students. The pretensions and conceits of this or that species can readily be ignored. There are, after-all, so many worlds about which an extraterrestrial biologist must know. It will be enough if a few salient and generic characteristics of life on yet another obscure planet are noted for the cavernous recesses of the galactic archives.