Définition : the air-filled cavity within the skull of vertebrates that lies between the outer ear and the inner ear. It is linked to the pharynx (and therefore to outside air) via the Eustachian tube and in mammals contains the three ear ossicles, which transmit auditory vibrations from the outer ear (via the tympanum) to the inner ear
Définition : where activity is distributed approximately evenly throughout the 24 h of the daily cycle, or when significant amounts of activity, particularly feeding and/or traveling, occur within both the light and dark portions of that cycle.
Définition : Hydrofoils, or fins, are used to push against the water to create a normal force to provide thrust, propelling the animal through water. The reduction of fin cross-sectional area helps to minimize drag, and therefore increase efficiency. Regardless of size of the animal, at any particular speed, maximum possible lift is proportional to (wing area) x (speed)<sup>2</sup>. Dolphins and whales have large, horizontal caudal hydrofoils, while many fish and sharks have vertical caudal hydrofoils.
Définition : 1) Producing live offspring from within the body of the parent (Lincoln et al., 1998). 2) Development of an embryo within the body of the parent, in part, resources passing directly from parent to embryo (Barnes et al., 2006).
Définition : the method used by some animals (e.g. bats, dolphins and some whales) to determine the location of something by measuring the time it takes for an echo to return from it. These animals emit sound waves and listen for the echo, calculating the distance to the object from the time lapse between sound emission and the echo returning.
Définition : Solitary animals are those that spend a majority of their lives without others of their species, with possible exceptions for mating and raising their young. Antonyms for a solitary animal include a social animal or a colonial animal.
Définition : Solitary animals are those that spend a majority of their lives without others of their species, with possible exceptions for mating and raising their young. Antonyms for a solitary animal include a social animal or a colonial animal.
Définition : where individuals of the same species (conspecifics), maintain spatial proximity with one another over time with mechanisms of social attraction
Définition : Relative to pinhole eyes, lens eyes have greatly improved resolution and image brightness. The lens converges incoming rays of light, thereby reducing the angle over which each photoreceptor receives light, and forming an image focused on the retina. Most lens eyes have "accommodation"; they can focus an image either by physically moving the lens toward or away from the retina or by using eye muscles to adjust the shape of the lens.