Ann Haven Morgan

"... The two problems which face every organism are those of maintaining its own life and continuing its race. Its youth is devoted entirely to satisfying its individual needs for food and safety; its adult life is devoted to the race, but the necessities of the individual are still satisfied though they may be secured in an entirely different way. The immature life of is aquatic, and to it all adjustments concerned with food or safety are exclusively confined. The mature or adult life is aerial. It is solely devoted to reproduction. There is no provision for food or for other means of lengthening its life. It gives an opportunity for studying ways of getting a living which have been completely isolated from ways of reproducing."

"At Kartabo the waters of the meet those of the and soon join the great lake-like flowing north through the low lying country of British Guiana until it runs into the sea at . These rivers are hedged in by the jungle whose undergrowth has invaded the border waters in a persistent attempt to gain more territory. roots swing so far out from the banks that fish swim in and out among them. Moccamoccas, the giant s, have grown out still further. Their clublike stems standing in close rank provide on gigantic scale the kind of animal shelter furnished in more modest form by our own and s. Many slow flowing creeks feed into these larger streams but their mouths are hidden by creepers, tangles of mangrove, and prickly shrubs, and if the currents are gentle enough they are choked by lush growths of '. … Even at Kartabo Point the daily tides are insistent reminders of the ocean forty miles away.The low tide lay bare stretches of muck and ooze, silt and silty sand ... the likely dwelling place of the burrowing and crawling Mayflies ..."

"Different waters hold their own special communities; the dainty glen stream shelters companies of in its swift riffles; pond shallows and meadow brooks are the homes of lurking s; and wayside puddles are populous with s and s. In all these places living things must contend with winter cold and summer drought, with storms and flood waters. In winter the pond populations drop to the bottom, frogs and turtles dig under mud and broken plants, s hide under banks to come out with every warm spell, and fresh water sponges are packed in tough covered capsules. In summer when its own pool dries up the flies to some other pond but many burrow into the mud bottom and endure the drought as best they can."

"Among the s and the water weeds of the shallows, lurk es, s, mud minnows, and young . All of these forage upon snails, crustaceans, and insect larvæ, especially the tempting mayfly nymphs which they find there. s float with their heads just out of water; of all frogs these belong most thoroughly in the pond. Equally at home in it are the painted turtles, and the spotted turtles often found with them … In May and June stumps and floating logs usually carry a load of one kind or the other. They forage in the shallows taking a heavy toll of tadpoles, snails, dragonflies—a miscellaneous bill-of-fare which they always eat under water. Snapping turtles frequent these waters also, catching anything within reach of the lightning-quick thrusts of their heads—fishes, tadpoles, frogs, or crayfishes, as well as the smaller game of insects and worms."

"s are transparent microscopic animals which live in fresh or salt water. They abound in the surface waters of great lakes, and swarm through the shallows of ponds and bogs; there is scarcely any stand of soft water, whether transient puddle or rain-barrel or fountain-basin, where rotifers can not be found. They live in ponds and lakes, providing a large part of the food for small s and worms and are thus indirectly a large source of food for fishes."

"es posses much more beauty and interest than their reputation credits them with. Most of them are marked with concealing colors and patterns, browns, greens, and blacks, picturing upon them the broken shadows and water-soaked leaves of their natural background and hiding them in it. They are sensitive to the slightest vibration of the water, to shadows passing over them, and to small changes in the water around them. Their whole set up is one of exquisite efficiency for their mode of living. … The external features most essential to a leech are the strong muscular suckers at each end of its body and the sucking mouth which which may or may not be armed with jaws … Leeches are segmented worms like bristleworms and common earthworms and belong to the Phylum '."

"As the spawning season approaches, fishes move toward the shores of ponds and lakes or upstream in the creeks. Some of them, such as perch and sunfish, only swim in among nearby weeds or protecting stones. The journeys vary from such short ones to the famous migrations of river salmon, extending over hundreds of miles; but they all end at spawning grounds or nesting sites. During this time color differences between male and female appear or become more marked."

"In most cold winters there is plenty of snow, and this is the greatest aid to wintering insects."

"Crickets.—Crickets, like grasshoppers, vary in their winter habits. Some live over the winter in the ; others hibernate as s. Nymphs of the , Gryllus assimilis pennsylvanicus (which has a short ), hibernate beneath stones ..."

"… Wherever animals live, in fresh water, salt water, or on land, their body fluids are similar; all are salty. In marine invertebrates, whether es or s, the body fluids are practically filtered sea water."

"The s () of s repeat the essentials of kidney form and function, tubules closely associated with blood and body fluid, each one a guardian of the content of the blood. There are two kidneys in nearly every segment of the earthworm ..."

". The power to regrow lost parts permits to survive and even to multiply after injury. Three planarians may live and flourish because one was cut into three pieces. All ns are aquatic. A considerable number live in fresh water and a few on moist soil. Most of them are marine."

"Feeding. The majority of ns are carnivorous. The smaller fresh-water ones feed upon s and worms that are nearly microscopic, the larger one on s, s and , often on their softened remains. Even in quiet waters they can detect juicy meat two or three feet away."

"... s feed upon microorganism from the muck and water of the bottom and in turn are consumed by es, s and mankind."

"... Darwin ... became the official naturalist on the five-year voyage of the "" (1831–1836) ... ... He also read the essay in which Malthus told of the human populations that became too large for the space available to them (1838). This suggested a plan. Some organism must be winnowed out by their natural surroundings; thus, others would be benefited. There would be natural selection."

"... Although she carried on most of her research in the northeastern United States, she spent the summer of 1926 working in at the Tropical Laboratory in Kartabo. Although limnology was her special subject—on which wrote a useful book, Field Book of Ponds and Streams (1930)—Morgan was also interested in many other facets of zoology, particularly hibernating animals. Her Field Book of Animals in Winter (1939) reflected this interest. In 1949 the ' made it into an educational film. She was also interested in conservation and ecology.."

"Morgan's views concerning animal and human interdependence place her among a select group of strong conservationists, of whom the most renowned is probably Rachel Carson ..."