Topic 38: Research

There have never been so many people living in cities in quake zones because the worse the damage can be from a big quake, bringing fires, tsunamis, and the loss of life, property, and maybe an entire city.

We understand how earthquakes happen but not exactly where or when they will occur. Until recently, quakes seemed to occur at random. In Japan, government research is now showing that quakes can be predicted. At the Earthquake Research Institute, University of Tokyo, Koshun Yamaoka says earthquakes do follow a pattern—pressure builds in a zone and must be released. But a colleague, Naoyuki Kato, adds that laboratory experiments indicate that a fault slips a little before it breaks. If this is true, predictions can be made based on the detection of slips.

Research in the U.S. may support Kato’s theory. In Parkfield, California earthquakes occur about every 22 years on the San Andreas fault. In the 1980s, scientists drilled into the fault and set up equipment to record activity to look for warning signs. When an earthquake hit again, it was years off schedule. At first the event seemed random but scientists drilled deeper. By 2005 they reached the bottom of the fault, two miles down, and found something. Data from two quakes reported in 2008 show there were two “slips’—places where the plates widened—before the fault line broke and the quakes occurred.

We are learning more about these destructive events every day. In the future we may be able to track earthquakes and design an early-warning system. So if the next great earthquake does happen in Tokai, about 100 miles southwest of Tokyo, as some scientists think, the citizens of Tokai may have advance warning.

(Adapted from Reading Explorer 3, Nancy Douglas et al., 2010)

All birds have feathers, and feathers are unique to birds. No other major group of animals is so easy to categorize. All birds have wings, too, but wings are not (1) ___________ to birds. Many adaptations are found in both feathers and wings. Feathers form the soft down of geese and ducks, the long showy plumes of ostriches and egrets, and the strong flight feathers of eagles and condors. Wings (2) _____________ from the short, broad ones of chickens, who seldom fly, to the long slim ones of albatrosses, who spend almost all their lives soaring on air currents. In penguins, wings have been modified (3) ________ flippers, and feathers into a waterproof covering. In kiwis, the wings are almost impossible to detect. Yet diversity among birds is no so striking as it is among mammals. The (4) ___________ between a hummingbird and a penguin is immense, but hardly as startling as that between a bat and a whale. It is variations in details rather than in fundamental patterns (5) _____________ have been important in the adaptation of birds to many kinds of ecosystems.

(www.studfiles.ru/preview/4467344)

Insects’ lives are very short and they have many enemies but they must survive long enough to breed and perpetuate their kind. The less insect-like they look, the better their chance of survival. To look “inedible” by imitating plants is a way frequently used by insects to survive. Mammals rarely imitate plants, but many fish and invertebrates do.

The stick caterpillar is well named. It is hardly distinguishable from a brown or green twig. This caterpillar is quite common and can be found almost anywhere in North America. It is also called “measuring worm” or “inchworm”. It walks by arching its body, then stretching out and grasping the branch with its front feet then looping its body again to bring the hind fed forward. When danger threatens, the stick caterpillar stretches its body away from the branch at an angle and remains rigid and still, like a twig, until the danger has passed.

Walking sticks, or stick insects, do not have to assume a rigid, twig-like pose to find protection: they look like inedible twigs in any position. There are many kinds of walking sticks, ranging in size from the few inches of the North American variety to some tropical species that may be over a foot long. When at rest their front legs are stretched out, heightening their camouflage. Some of the tropical species are adorned with spines or ridges, imitating the thorny bushes or trees in which they live.

Leaves also seem to be a favorite object for insects to imitate. Many butterflies can suddenly disappear from view by folding their wings and sitting quietly among the plants that they resemble.

The walnut tree produces wood that is used for countless purposes, and is considered the finest wood in the world. The wood is easy to work with, yet it is very hard and durable - and when it is polished, it produces a rich, dark luster. It also shrinks and swells less than any other wood, which makes it especially desirable for fine furniture, flooring, and even gun stocks.

In fact, just about every part of the walnut is unusually hard and strong. The nut of the tree is encased inside a very hard shell, which itself is enclosed in a leathery outer covering called a husk. It requires real effort to break through those layers to get at the tasty meat inside.

Yet every part of the walnut is useful to people. The outer husk produces a dark reddish stain that is hard to remove from the hands of the person who opens the nut, and this pigment is widely used in dyes and wood stains. The inner shell is used as an abrasive to clean jet engines. And the meat of the nut is extensively used in cooking, ice cream, flavourings - and just eaten raw.

Walnut trees exude a chemical into the soil near their roots which can be poisonous to some trees and shrubs. Fruit trees, for example, will not survive if planted too close to a walnut. Many other plants, such as maple trees or ivy, are not affected by the walnut’s presence, and are well-suited to grow in its vicinity.