Table 1.

Examples of species with different aspects of movement variation, their causes and consequences

Movement types & System	Variation cause	Variation consequence
Dispersal tendency. Western bluebird (Sialia mexicana) populations are currently re-expanding across the United States, coming into contact with a closely related species, mountain bluebirds [10].	Male western bluebirds differ consistently in their level of aggression, with dispersing males more aggressive than philopatric males. More aggressive males are also more likely to win in competitive interactions for territories (even in interactions with mountain bluebirds) but provide little parental care to their offspring (causing high offspring mortality).	Dispersing western bluebirds (who tend to be aggressive) are colonizing into mountain bluebird habitat, outcompeting them, and thus expanding the western bluebird range. Aggressive males are replaced over time by non-aggressive males who produce more surviving offspring and are thus at a selective advantage.
Dispersal distance. Cane toads (Rhinella marina) were introduced to Australia in 1935 and have been rapidly spreading across the country [11, 12].	Individuals on the edge of the population range (those that arrive earlier to a new area) move further each day and spend more time dispersing than toads in the center of the population range (those that arrive later).	The spatial assortment by dispersal ability, coupled with a genetic basis for dispersal in cane toads, has caused the population spread to accelerate over time.
Foraging route. Bumble-bees (Bombus impatiens) exhibit trapline foraging, repeatedly visiting the same series of plants. Trapline routes differ across individuals and some individuals forage locally instead of traplining [13].	Each bee learns a specific trapline in a few hours, suggesting that different early experiences leads to individual differences in trapline routes.	Bee foraging behavior influences pollination patterns; traplining increases pollen dispersal distance compared to local foraging.
Foraging habitat selection. Spadefoot toad tadpoles (Spea multiplicatus)	Tadpoles prefer food associated with their natal habitat/diet.	Related tadpoles with the same natal habitat prefer the same food, leading to associate with kin even in the absence of explicit recognition.
Migration frequency. Pacific leatherback turtles (Dermochelys coriacea) spend most of their time in open ocean foraging areas; females migrate every 2–7 years to nesting beaches where they reproduce [14].	Remigration interval (the number of years between successive migrations) varies with local foraging conditions. La Niña years (lower sea surface temperatures) increase the upwelling of nutrient-rich water, leading to faster acquisition of resources for breeding and thus shorter remigration intervals.	Variable remigration intervals leads to variation in annual egg production at the population level.
Migration tendency. Roach (Rutilus rutilus) migrate between lakes and streams, driven by seasonal changes in trade-offs between predation risk and forage opportunities (lakes have more food but also more predators) [15, 16].	Individuals with higher body condition are more likely to migrate into streams, foregoing further foraging opportunities in exchange for lower predation risk, while starved fish are more likely to remain in lakes, prioritizing access to food.	Changes in the number of fish migrating from year to year change the predation pressure on zooplankton in lakes, altering zooplankton size structure. Fewer migrating fish lead to a later peak in zooplankton biomass, thus shifting seasonal dynamics of both zooplankton and phytoplankton.