Atlantic white-sided dolphinThe Atlantic white-sided dolphin (Lagenorhynchus acutus) is a distinctively coloured dolphin found in the cool to temperate waters of the North Atlantic Ocean. The dolphin is slightly larger than most other oceanic dolphins. It is just over a meter in length at birth, growing to about (males) and (females) at maturity. It weighs 180–230 kg (400- 510 lb) once fully-grown. Females reach sexual maturity at between 6 and 12 years, and males between 7 and 11 years.
Pygmy sperm whaleThe pygmy sperm whale (Kogia breviceps) is one of two extant species in the family Kogiidae in the sperm whale superfamily. They are not often sighted at sea, and most of what is known about them comes from the examination of stranded specimens. The pygmy sperm whale was first described by naturalist Henri Marie Ducrotay de Blainville in 1838. He based this on the head of an individual washed up on the coasts of Audierne in France in 1784, which was then stored in the Muséum d'histoire naturelle.
SocialitySociality is the degree to which individuals in an animal population tend to associate in social groups (gregariousness) and form cooperative societies. Sociality is a survival response to evolutionary pressures. For example, when a mother wasp stays near her larvae in the nest, parasites are less likely to eat the larvae. Biologists suspect that pressures from parasites and other predators selected this behavior in wasps of the family Vespidae. This wasp behaviour evidences the most fundamental characteristic of animal sociality: parental investment.
Dolphin drive huntingDolphin drive hunting, also called dolphin drive fishing, is a method of hunting dolphins and occasionally other small cetaceans by driving them together with boats and then usually into a bay or onto a beach. Their escape is prevented by closing off the route to the open sea or ocean with boats and nets. Dolphins are hunted this way in several places around the world including the Solomon Islands, the Faroe Islands, Peru, and Japan, which is the most well-known practitioner of the method.
Pacific white-sided dolphinThe Pacific white-sided dolphin (Lagenorhynchus obliquidens), also known as the hookfin porpoise, is an active dolphin found in the cool or temperate waters of the North Pacific Ocean. The Pacific white-sided dolphin was named by Smithsonian mammalogist Theodore Nicholas Gill in 1865. It is morphologically similar to the dusky dolphin, which is found in the South Pacific. Genetic analysis by Frank Cipriano suggests the two species diverged around two million years ago.
Whale vocalizationWhales use a variety of sounds for communication and sensation. The mechanisms used to produce sound vary from one family of cetaceans to another. Marine mammals, including whales, dolphins, and porpoises, are much more dependent on sound than land mammals due to the limited effectiveness of other senses in water. Sight is less effective for marine mammals because of the particulate way in which the ocean scatters light. Smell is also limited, as molecules diffuse more slowly in water than in air, which makes smelling less effective.
Animal trainingAnimal training is the act of teaching animals specific responses to specific conditions or stimuli. Training may be for purposes such as companionship, detection, protection, and entertainment. The type of training an animal receives will vary depending on the training method used, and the purpose for training the animal. For example, a seeing eye dog will be trained to achieve a different goal than a wild animal in a circus. In some countries animal trainer certification bodies exist.
CountershadingCountershading, or Thayer's law, is a method of camouflage in which an animal's coloration is darker on the top or upper side and lighter on the underside of the body. This pattern is found in many species of mammals, reptiles, birds, fish, and insects, both in predators and in prey. When light falls from above on a uniformly coloured three-dimensional object such as a sphere, it makes the upper side appear lighter and the underside darker, grading from one to the other.
Polychlorinated biphenylPolychlorinated biphenyls (PCBs) are highly carcinogenic chemical compounds, formerly used in industrial and consumer products, whose production was banned in the United States by the Toxic Substances Control Act in 1976 and internationally by the Stockholm Convention on Persistent Organic Pollutants in 2001. PCBs are organic chlorine compounds with the formula C12H10−xClx; they were once widely used in the manufacture of carbonless copy paper, as heat transfer fluids, and as dielectric and coolant fluids for electrical equipment.
Rostrum (anatomy)Rostrum (from Latin rostrum, meaning beak) is a term used in anatomy for a number of phylogenetically unrelated structures in different groups of animals. In crustaceans, the rostrum is the forward extension of the carapace in front of the eyes. It is generally a rigid structure, but can be connected by a hinged joint, as seen in Leptostraca. Among insects, the rostrum is the name for the piercing mouthparts of the order Hemiptera as well as those of the snow scorpionflies, among many others.