The Red Queen Hypothesis
The Red Queen Hypothesis
The Red Queen Hypothesis was formulated by Van Valen in 1973, and its original purpose was to give an understanding of the adaptation dynamics between species (Vermeij and Roopnarine, 2013). The principles of The Red Queen Hypothesis is clearly formulated in McCune (1982), that states ”all taxa are running on a treadmill powered by an environment which deteriorates at a stochastically constant rate. The result is that an ancient taxon is no better adapted than a younger one; it has just been running in place longer”. Basically it means that, in order for species to survive they need to evolve fast enough to have fitness that can compete with predators, parasites etc., who also are continually evolving (Castrodeza, 1979; Futuyma, 2013, p. 172). The Red Queen Hypothesis mainly acts on species level and below (McCune, 1982), and equals a zero-sum game, everytime a species gain fitness, it is counterbalanced by an equal gain of all other interacting species, and no species ever wins (Stenseth, 1979). For species to exist, they must minimally be well-designed, and if better designed they might be more suited for future circumstances (McCune, 1982), maladapted species will be eliminated by natural selection (Castrodeza, 1979).
Organisms evolve due to changes (Van Valen, 1969), when environmental conditions changes, …show more content…
species who was optimally adapted through selection to these previously conditions, will need to evolve further (Rosenzweig et al., 1987). If living in a continuously fluctuating environment, the genetic recombination of alleles might continually create genotypes that a selective favorable. These can be favorable or unfavorable in future generations (Salathé et al., 2009).
Butterflies are among the many groups of herbivorous organisms that coevolve with plants (Ehrlich and Raven, 1964). Butterflies need to feed on the plants that are available in their ecological range, and some species overlaps geographically and ecologically in their feeding ranges (Deteier, 1952).
Multiple species of butterflies and moths lay their eggs on certain plants (Merz 1959 in Ehrlich and Raven, 1964), when the larva emerge it will feed on this plant, and in some cases consume all of it (Ehrlich and Raven, 1964). As a response, selection will modify the plant species in order to limit the acceptability for larva. This was the case with the moth larva of Lasiocampa quercus who normally feed along the edge of leaves of holly (Ilex aquifolium), but after modifications that gave the plant sharper toothed leaves it was not possible for the larva to feed on it (Ehrlich and Raven, 1964).
Adaptive Radiation
Adaptive radiation is an evolutionary process where a species diversity, leading to origination of multiple species which are adapted to different ecological environments (Rasmussen, 2005, p.
23). About ten million years after the dinosaurs died out, mammals underwent adaptive radiation, where animals as different as bats, whales and larger dogs originated (Stanley, 1987, p. 8). Adaptive radiation is not a continuous process, it happens in steps when the ecological conditions favors it (Vermeij and Roopnarine, 2013), like when new niches are created due to climatic changes or tectonic events (Stanley, 1987 p. 21; Gillespie,
2004).
When Madagascar became isolated from India, its flora and fauna underwent adaptive radiation. Because Madagascar have a large surface area with a varied microclimates and habitats, its long-term geographical isolation gave rise to more than 40 species of lemuriforms that descended from a single common ancestor that colonized Madagascar via transoceanic dispersal from Africa (Yoder and Yang 2004). Similarly, groups of New World monkeys and guinea pigs originated in South America during the Tertiary from species that invaded through transoceanic dispersal from Africa (Futuyma, 2013, p. 147).
The Red Queen Hypothesis was formulated by Van Valen in 1973, and its original purpose was to give an understanding of the adaptation dynamics between species (Vermeij and Roopnarine, 2013). The principles of The Red Queen Hypothesis is clearly formulated in McCune (1982), that states ”all taxa are running on a treadmill powered by an environment which deteriorates at a stochastically constant rate. The result is that an ancient taxon is no better adapted than a younger one; it has just been running in place longer”. Basically it means that, in order for species to survive they need to evolve fast enough to have fitness that can compete with predators, parasites etc., who also are continually evolving (Castrodeza, 1979; Futuyma, 2013, p. 172). The Red Queen Hypothesis mainly acts on species level and below (McCune, 1982), and equals a zero-sum game, everytime a species gain fitness, it is counterbalanced by an equal gain of all other interacting species, and no species ever wins (Stenseth, 1979). For species to exist, they must minimally be well-designed, and if better designed they might be more suited for future circumstances (McCune, 1982), maladapted species will be eliminated by natural selection (Castrodeza, 1979).
Organisms evolve due to changes (Van Valen, 1969), when environmental conditions changes, …show more content…
species who was optimally adapted through selection to these previously conditions, will need to evolve further (Rosenzweig et al., 1987). If living in a continuously fluctuating environment, the genetic recombination of alleles might continually create genotypes that a selective favorable. These can be favorable or unfavorable in future generations (Salathé et al., 2009).
Butterflies are among the many groups of herbivorous organisms that coevolve with plants (Ehrlich and Raven, 1964). Butterflies need to feed on the plants that are available in their ecological range, and some species overlaps geographically and ecologically in their feeding ranges (Deteier, 1952).
Multiple species of butterflies and moths lay their eggs on certain plants (Merz 1959 in Ehrlich and Raven, 1964), when the larva emerge it will feed on this plant, and in some cases consume all of it (Ehrlich and Raven, 1964). As a response, selection will modify the plant species in order to limit the acceptability for larva. This was the case with the moth larva of Lasiocampa quercus who normally feed along the edge of leaves of holly (Ilex aquifolium), but after modifications that gave the plant sharper toothed leaves it was not possible for the larva to feed on it (Ehrlich and Raven, 1964).
Adaptive Radiation
Adaptive radiation is an evolutionary process where a species diversity, leading to origination of multiple species which are adapted to different ecological environments (Rasmussen, 2005, p.
23). About ten million years after the dinosaurs died out, mammals underwent adaptive radiation, where animals as different as bats, whales and larger dogs originated (Stanley, 1987, p. 8). Adaptive radiation is not a continuous process, it happens in steps when the ecological conditions favors it (Vermeij and Roopnarine, 2013), like when new niches are created due to climatic changes or tectonic events (Stanley, 1987 p. 21; Gillespie,
2004).
When Madagascar became isolated from India, its flora and fauna underwent adaptive radiation. Because Madagascar have a large surface area with a varied microclimates and habitats, its long-term geographical isolation gave rise to more than 40 species of lemuriforms that descended from a single common ancestor that colonized Madagascar via transoceanic dispersal from Africa (Yoder and Yang 2004). Similarly, groups of New World monkeys and guinea pigs originated in South America during the Tertiary from species that invaded through transoceanic dispersal from Africa (Futuyma, 2013, p. 147).