210 résultats pour "biology"
- Feather (bird anatomy) - biology.
- Diseases of Plants - biology.
- Rabbits and Hares - biology.
- Death and Dying - biology.
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Great White Shark - biology.
The great white shark is a rare species that takes long to reach sexual maturity and that reproduces slowly. Populations cannot easily increase if depleted. The biggestthreat to great whites comes from being unintentionally caught in fishing nets. Some targeted fisheries and sport fishing for great white sharks also occur. Trade ingreat white shark products includes the jaws (which can sell for thousands of dollars as curios), individual teeth, and leather from its skin. Fins from all sharks, in...
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Dolphin (aquatic mammal) - biology.
Scientists have observed dolphins displaying three types of caregiving behaviors: standing by, excitement, and supporting. In standing-by behavior, dolphins remain inthe vicinity of an injured or ill companion without offering aid. In excitement behavior, dolphins swim swiftly in circles around an injured dolphin, responding aggressivelytoward threats to the injured animal. For instance, they may bite harpoon lines or charge boats that come too close to the animal. In supporting behavior, one or...
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Butterflies and Moths - biology.
The smallest butterflies are certain blues that have wingspans of a mere 0.7 cm (0.25 in). The largest are the female giant birdwings of Papua New Guinea, whichmeasure up to 30 cm (12 in) across. Moths range in size from tiny Microlepidoptera, several groups of small moths with wings no more than 0.16 cm (0.06 in) across, togiant silk moths, such as the atlas moth, which may exceed 30 cm (12 in) in wingspan. IV REPRODUCTION AND LIFE CYCLE Butterflies locate potential mates by sight, identifyin...
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Animal Courtship and Mating - biology.
activity. These animals frequently copulate in water, and the penis helps transfer sperm before it is carried away by the currents Ostriches and rheas also contain apenis within the cloaca. Virtually all snakes and lizards display yet another variation of internal fertilization. Located in the tail are two penises, called hemepenes, which are covered by spinesand knobs that help lock it into place during mating. The male uses one hemepene at a time for copulation. Male salamanders secrete large...
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- Poison Ivy, Poison Oak, and Poison Sumac - biology.
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Anthropology.
humans, such as tools, pottery, and buildings) and human fossils (preserved bones). They also examine past environments to understand how natural forces, such as climate and available food, shaped the development of human culture. Some archaeologists study cultures that existed before the development of writing, a time knownas prehistory . The archaeological study of periods of human evolution up to the first development of agriculture, about 10,000 years ago, is also called paleoanthropology....