Quick Answer: What Animals Are R-Strategists?

What is an R-strategist species?

R-selected species, also called r-strategist, species whose populations are governed by their biotic potential (maximum reproductive capacity, r).

Wilson; K-selected species—that is, species whose population sizes fluctuate at or near their carrying capacity (K)—make up the second strategy..

Are Lions R or K-selected?

Common examples of k-strategists species include humans, lions and whales.

Are dogs K or R strategists?

Indeed, one can think of a given organism as an “r-strategist” or a “K-strategist” only relative to some other organism; thus statements about r and K selection are invariably comparative. Cats and dogs are r-selected compared to humans, but K-selected compared to mice and rats.

Are trees R or K strategists?

For instance, trees have traits such as longevity and strong competitiveness that characterise them as K-strategists. In reproduction, however, trees typically produce thousands of offspring and disperse them widely, traits characteristic of r-strategists.

What are examples of R-selected species?

Typical examples of r-species are mice, rabbits, weeds and bacteria, which have a lot of offspring, but a short life expectancy. Examples of organisms undergoing K-selection are tortoises, elephants, people, and sequoia trees: their offspring are few but long-lived.

Are Squirrels R strategists?

In contrast, red squirrels, with a lower reproductive rate, have evolved more as “K strategists.” Red squirrels have specialized food habits, are highly territorial, and apparently have a rather complex social structure (Layne, 1954; Smith, 1968; Kemp and Keith, 1971 ).

Which animal type could be described as R-selected?

Many aquatic organisms like some species of fish, frogs, and salamanders have relatively short lifespans, reach sexual maturity rapidly, and reproduce by releasing hundreds of eggs with only a few surviving to adulthood. Arthropods like insects, spiders, and crustaceans are also R-selected.

What does R stand for in r-selected species?

A whale tends for a single calf. r-selection: On one extreme are the species that are highly r-selected. r is for reproduction. Such a species puts only a small investment of resources into each offspring, but produces many such low effort babies.

Are bacteria R selected?

R-selected organisms, those emphasizing a fast growth rate, high number of offspring, include rabbits, bacteria, salmon, plants such as weeds and grasses, etc.

Why are r-selected species opportunists?

Why do r-selected species tend to be opportunists? They reproduce and disperse rapidly when conditions are favorable or when disturbance opens up and a new habitat or niche for invasion. … They tend to reproduce later in life and have a small number of offspring with fairly long life spans.

Are Squirrels R selected or K selected?

Most invertebrates are r-selected compared to vertebrates. Tree squirrels are K-selected compared to ground squirrels but rodents are r-selected compared to elephants, etc.

Are Snakes r selected species?

Despite having characteristics of both R and K strategists, Eastern Milk Snakes are R strategists. Mainly because of the fact that they do not care for their young, but also because the baby snakes mature fairly quickly.

Are frogs r selected species?

Other examples of r-selected species include frogs, bacteria, and dandelions. … R-selected species produce so many offspring because it is not likely that many of them will survive.

Are cats R strategists?

r selected species are also known as r strategists and opportunistic species. They practice big-bang reproduction, AKA semelparity. … Cats are r-selected compared to humans, and K-selected compared to cockroaches.

Why are humans K-selected species?

K-selected species possess relatively stable populations fluctuating near the carrying capacity of the environment. These species are characterized by having only a few offspring but investing high amounts of parental care. Elephants, humans, and bison are all k-selected species.

Are birds R or K strategists?

K-selected species are characterized by long gestation periods lasting several months, slow maturation (and thus extended parental care), and long life spans. … Examples of K-selected species include birds, larger mammals (such as elephants, horses, and primates), and larger plants.

What are K strategists R strategists?

The terms r-selection and K-selection are used by ecologists to describe the growth and reproduction strategies of organisms. r-selected species have a high growth rate but low survivability (“cheap” offspring) K-selected species have a low growth rate but high survivability (“expensive” offspring)

Are invasive species R or K-selected?

Biologists characterize most invasive species as r-selected. … While K-selected species exhibit low mortality, the majority of an r-selected species’ offspring are sure to perish; however, a few are likely to navigate the world successfully, mature and reproduce.

Are humans R or K?

Both across and within species, r and K strategists differ in a suite of correlated characteristics. Humans are the most K of all. K’s supposedly have a longer gestation period, a higher birthweight, a more delayed sexual maturation, a lower sex drive, and a longer life.

Why are rabbits r-selected species?

So this begs the question are rabbits truly prolific, and why? In Page 2 the 1960s two ecologists came up with r/K selection theory. It relates to parental investment and reproductive strategies adopted by species in order to advance its kind into the future. … And they have the ability to reproduce rapidly.

What does R stand for in ecology?

The first variable is r (the intrinsic rate of natural increase in population size, density independent) and the second variable is K (the carrying capacity of a population, density dependent).