f) Some animals move long distances regularly in
Answers
Answer:
Animal migration refers to the movement of animals over a long distance, usually in line with changes in the seasons. This movement exists in all the main animal groups, which includes birds, fish, insects, amphibians, crustaceans, mammals, and reptiles.
ANSWER:
Migration can take very different forms in different species, and as such there is no simple accepted definition of migration. One of the most commonly used definitions, proposed by Kennedy is
Migratory behavior is persistent and straightened out movement effected by the animal’s own locomotory exertions or by its active embarkation upon a vehicle. It depends on some temporary inhibition of station keeping responses but promotes their eventual disinhibition and recurrence.
Migration encompasses four related concepts: persistent straight movement; relocation of an individual on a greater scale (both spatially and temporally) than its normal daily activities; seasonal to-and-fro movement of a population between two areas; and movement leading to the redistribution of individuals within a population. Migration can be either obligate, meaning individuals must migrate, or facultative, meaning individuals can "choose" to migrate or not. Within a migratory species or even within a single population, often not all individuals migrate. Complete migration is when all individuals migrate, partial migration is when some individuals migrate while others do not, and differential migration is when the difference between migratory and non-migratory individuals is based on age or sex (for example).
While most migratory movements occur on an annual cycle, some daily movements are also referred to as migration. Many aquatic animals make a diel vertical migration, travelling a few hundred meters up and down the water column, while some jellyfish make daily horizontal migrations, traveling a few hundred meters across a lake.
Irregular (non-cyclical) migrations such as irruptions can occur under pressure of famine, overpopulation of a locality, or some more obscure influence.[8]
Seasonal migration is the movement of various species from one habitat to another during the year. Resource availability changes depending on seasonal fluctuations, which influence migration patterns. Some species such as Pacific salmon migrate to reproduce; every year they swim upstream to mate and then return to the ocean. Temperature is a driving factor of migration that is dependent on the time of year. Many species, especially birds, migrate to warmer locations during the winter to escape poor environmental conditions.
Circadian migration is where birds utilize circadian rhythm (CR) to regulate migration in both the fall and the spring. In circadian migration clocks of both circadian (daily) and circannual (annual) patterns are utilized to determine the birds’ orientation in both time and space as they migrate from one destination to the next. This type of migration is advantageous in birds that during the winter remain close to the equator, and also allows the monitoring of the auditory and spatial memory of the birds’ brain to remember an optimal site of migration. These birds also have timing mechanisms that provide avians with the distance required to travel in order to reach their destination. To regulate the migration patterns of these birds, the mammalian circadian clock is utilized. This clock allows birds to determine when the appropriate time is to migrate, which location will best help them regulate their metabolism, and whether land or water travel will be most advantageous.
Tidal migration is the use of tides by organisms to move periodically from one habitat to another. This type of migration is often used in order to find food or mates. Tides can carry organisms horizontally and vertically for as little as a few nanometers to even thousands of kilometers. The most common form of tidal migration is to and from Intertidal zone during daily tidal cycles.These zones are often populated by many different species and are nutrient rich. Organisms like crabs, nematodes, small fish, corals, and other species cycle to these areas as the tides rise and fall typically about every twelve hours. The cycle movements are associated with foraging of marine and bird species. Typically, during low tide smaller or younger species will emerge to forage because they can survive in the shallower water and have less chance of being preyed upon. During high tide, larger species can be found due to the deeper water and nutrient upwelling from the tidal movements. Tidal migration is often facilitated by ocean currents.