Introduced species

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Cattle Bos primigenius taurus introduced but not naturalized worldwide Bubikon.JPG
Cattle Bos primigenius taurus introduced but not naturalized worldwide
Sweet clover (Melilotus sp.), introduced and naturalized in the Americas from Europe as a forage and cover crop Melilotus alba bgiu.jpg
Sweet clover (Melilotus sp.), introduced and naturalized in the Americas from Europe as a forage and cover crop

An introduced species, alien species, exotic species, adventive species, immigrant species, foreign species, non-indigenous species, or non-native species is a species living outside its native distributional range, but which has arrived there by human activity, directly or indirectly, and either deliberately or accidentally. Non-native species can have various effects on the local ecosystem. Introduced species that become established and spread beyond the place of introduction are considered naturalized. The process of human-caused introduction is distinguished from biological colonization, in which species spread to new areas through "natural" (non-human) means such as storms and rafting. The Latin expression neobiota captures the characteristic that these species are new biota to their environment in terms of established biological network (e.g. food web) relationships. Neobiota can further be divided into neozoa (also: neozoons, sing. neozoon, i.e. animals) and neophyta (plants).


The impact of introduced species is highly variable. Some have a substantial negative effect on a local ecosystem (in which case they are also classified more specifically as an invasive species), while other introduced species may have little or no negative impact (no invasiveness). Some species have been introduced intentionally to combat pests. They are called biocontrols and may be regarded as beneficial as an alternative to pesticides in agriculture for example. In some instances the potential for being beneficial or detrimental in the long run remains unknown. [1] [2] [3] The effects of introduced species on natural environments have gained much scrutiny from scientists, governments, farmers and others.

Terminology: introduced species and subsets

The formal definition of an introduced species from the United States Environmental Protection Agency is "A species that has been intentionally or inadvertently brought into a region or area. Also called an exotic or non-native species". [4] [5]

In the broadest and most widely used sense, an introduced species is synonymous with "non-native" and therefore applies as well to most garden and farm organisms; these adequately fit the basic definition given above. However, some sources add to that basic definition "and are now reproducing in the wild", [6] which means that species growing in a garden, farm, or house may not meet the criteria unless they escape and persist.

Subset descriptions

There are many terms associated with introduced species that represent subsets of introduced species, and the terminology associated with introduced species is now in flux for various reasons. Examples of these terms are "invasive", "acclimatized", "adventive", "naturalized", and "immigrant" species.

The term "invasive" is used to describe introduced species that cause ecological, economic, or other damage to the area in which they were introduced.

Acclimatized species are introduced species that have changed physically and/or behaviorally in order to adjust to their new environment. Acclimatized species are not necessarily optimally adjusted to their new environment and may just be physically/behaviorally sufficient for the new environment.

Adventive species are often considered synonymous with "introduced species", but this term is sometimes applied exclusively to introduced species that are not permanently established. [7]

Naturalized species are often introduced species that do not need human help to reproduce and maintain their population in an area outside their native range (no longer adventive), but that also applies to populations migrating and establishing in a novel environment (e.g.: in Europe, house sparrows are well established since early Iron Age though they originated from Asia).

Immigrant species are species that travel, sometimes by themselves, but often with human help, between two habitats. Invasiveness is not a requirement. [8]

Invasive species

Introduction of a species outside its native range is all that is required to be qualified as an "introduced species". Such species might be termed naturalized, "established", or "wild non-native species". If they further spread beyond the place of introduction and cause damage to nearby species, they are called "invasive species". The transition from introduction, to establishment and to invasion has been described in the context of plants. [9] Introduced species are essentially "non-native" species. Invasive species are those introduced species that spread widely or quickly and cause harm, be that to the environment, [10] human health, other valued resources, or the economy. There have been calls from scientists to consider a species "invasive" only in terms of their spread and reproduction rather than the harm they may cause. [11]

According to a practical definition, an invasive species is one that has been introduced and become a pest in its new location, spreading (invading) by natural means. The term is used to imply both a sense of urgency and actual or potential harm. For example, U.S. Executive Order 13112 (1999) defines "invasive species" as "an alien species whose introduction does or is likely to cause economic or environmental harm or harm to human health". [12] The biological definition of invasive species, on the other hand, makes no reference to the harm they may cause, only to the fact that they spread beyond the area of original introduction.

Some argue that "invasive" is a loaded word and harm is difficult to define. [6]

From a regulatory perspective, it is neither desirable nor practical to list as undesirable or outright ban all non-native species (although the State of Hawaii has adopted an approach that comes close to this). Regulations require a definitional distinction between non-natives that are deemed especially onerous and all others. Introduced "pest" species, that are officially listed as invasive, best fit the definition of an invasive species. Early detection and rapid response is the most effective strategy for regulating a pest species and reducing economic and environmental impacts of an introduction. [13]

In Great Britain, the Wildlife and Countryside Act 1981 prevents the introduction of any animal not naturally occurring in the wild or any of a list of both animals or plants introduced previously and proved to be invasive.

Nature of introductions

By definition, a species is considered "introduced" when its transport into an area outside of its native range is human mediated. Introductions by humans can be described as either intentional or accidental. Intentional introductions have been motivated by individuals or groups who either (1) believe that the newly introduced species will be in some way beneficial to humans in its new location or, (2) species are introduced intentionally but with no regard to the potential impact. Unintentional or accidental introductions are most often a byproduct of human movements and are thus unbound to human motivations. Subsequent range expansion of introduced species may or may not involve human activity.

Wheat Triticum introduced worldwide from its place of origin (Mesopotamia) Wheat-haHula-ISRAEL.JPG
Wheat Triticum introduced worldwide from its place of origin (Mesopotamia)

Intentional introductions

Species that humans intentionally transport to new regions can subsequently become successfully established in two ways. In the first case, organisms are purposely released for establishment in the wild. It is sometimes difficult to predict whether a species will become established upon release, and if not initially successful, humans have made repeated introductions to improve the probability that the species will survive and eventually reproduce in the wild. In these cases, it is clear that the introduction is directly facilitated by human desires.

Male Lophura nycthemera (silver pheasant), a native of East Asia that has been introduced into parts of Europe for ornamental reasons Male Silver Pheasant.jpg
Male Lophura nycthemera (silver pheasant), a native of East Asia that has been introduced into parts of Europe for ornamental reasons

In the second case, species intentionally transported into a new region may escape from captive or cultivated populations and subsequently establish independent breeding populations. Escaped organisms are included in this category because their initial transport to a new region is human motivated.

The widespread phenomena of intentional introduction has also been described as biological globalization.

Motivations for intentional introductions

Economic: Perhaps the most common motivation for introducing a species into a new place is that of economic gain. Non-native species can become such a common part of an environment, culture, and even diet that little thought is given to their geographic origin. For example, soybeans, kiwi fruit, wheat, honey bees, and all livestock except the American bison and the turkey are non-native species to North America. Collectively, non-native crops and livestock account for 98% of US food. [14] These and other benefits from non-natives are so vast that, according to the Congressional Research Service, they probably exceed the costs. [15]

Other examples of species introduced for the purposes of benefiting agriculture, aquaculture or other economic activities are widespread. [16] Eurasian carp was first introduced to the United States as a potential food source. The apple snail was released in Southeast Asia with the intent that it be used as a protein source, and subsequently to places like Hawaii to establish a food industry. In Alaska, foxes were introduced to many islands to create new populations for the fur trade. About twenty species of African and European dung beetles have established themselves in Australia after deliberate introduction by the Australian Dung Beetle Project in an effort to reduce the impact of livestock manure. The timber industry promoted the introduction of Monterey pine ( Pinus radiata ) from California to Australia and New Zealand as a commercial timber crop. These examples represent only a small subsample of species that have been moved by humans for economic interests.{{

The rise in the use of genetically modified organisms has added another potential economic advantage to introducing new/modified species into different environments. Companies such as Monsanto that earn much of their profit through the selling of genetically modified seeds has added to the controversy surrounding introduced species. The effect of genetically modified organisms varies from organism to organism and is still being researched today, however, the rise of genetically modified organisms has added complexity to the conversations surrounding introduced species.

Human enjoyment

Introductions have also been important in supporting recreation activities or otherwise increasing human enjoyment. Numerous fish and game animals have been introduced for the purposes of sport fishing and hunting. The introduced amphibian ( Ambystoma tigrinum ) that threatens the endemic California salamander ( Ambystoma californiense ) was introduced to California as a source of bait for fishermen. [17] Pet animals have also been frequently transported into new areas by humans, and their escapes have resulted in several introductions, such as feral Cats and Parrots.

Many plants have been introduced with the intent of aesthetically improving public recreation areas or private properties. The introduced Norway maple for example occupies a prominent status in many of Canada's parks. [18] The transport of ornamental plants for landscaping use has and continues to be a source of many introductions. Some of these species have escaped horticultural control and become invasive. Notable examples include water hyacinth, salt cedar, and purple loosestrife.

In other cases, species have been translocated for reasons of "cultural nostalgia", which refers to instances in which humans who have migrated to new regions have intentionally brought with them familiar organisms. Famous examples include the introduction of common starlings to North America by the American Eugene Schieffelin, a lover of the works of Shakespeare and the chairman of the American Acclimatization Society, who, it is rumoured, wanted to introduce all of the birds mentioned in Shakespeare's plays into the United States. He deliberately released eighty starlings into Central Park in New York City in 1890, and another forty in 1891.

Yet another prominent example of an introduced species that became invasive is the European rabbit in Australia. Thomas Austin, a British landowner, had rabbits released on his estate in Victoria because he missed hunting them. A more recent example is the introduction of the common wall lizard (Podarcis muralis) to North America by a Cincinnati boy, George Rau, around 1950 after a family vacation to Italy. [19]

Addressing environmental problems

Intentional introductions have also been undertaken with the aim of ameliorating environmental problems. A number of fast spreading plants such as kudzu have been introduced as a means of erosion control. Other species have been introduced as biological control agents to control invasive species. This involves the purposeful introduction of a natural enemy of the target species with the intention of reducing its numbers or controlling its spread.

A special case of introduction is the reintroduction of a species that has become locally endangered or extinct, done in the interests of conservation. [20] Examples of successful reintroductions include wolves to Yellowstone National Park in the U.S., and the red kite to parts of England and Scotland. Introductions or translocations of species have also been proposed in the interest of genetic conservation, which advocates the introduction of new individuals into genetically depauperate populations of endangered or threatened species. [21]

Unintentional introductions

Unintentional introductions occur when species are transported by human vectors. Increasing rates of human travel are providing accelerating opportunities for species to be accidentally transported into areas in which they are not considered native. For example, three species of rat (the black, Norway and Polynesian) have spread to most of the world as hitchhikers on ships, and arachnids such as scorpions and exotic spiders are sometimes transported to areas far beyond their native range by riding in shipments of tropical fruit. This was seen during the introduction of Steatoda nobilis (Noble false widow) worldwide through banana shipments. [22] There are also numerous examples of marine organisms being transported in ballast water, one being the zebra mussel. Over 200 species have been introduced to the San Francisco Bay in this manner making it the most heavily invaded estuary in the world. [23] There is also the accidental release of the Africanized honey bees (AHB), known colloquially as "killer bees") or Africanized bee to Brazil in 1957 and the Asian carp to the United States. The insect commonly known as the brown marmorated stink bug (Halyomorpha halys) was introduced accidentally in Pennsylvania. Another form of unintentional introductions is when an intentionally introduced plant carries a parasite or herbivore with it. Some become invasive, for example, the oleander aphid, accidentally introduced with the ornamental plant, oleander.

Yet another unintentional pathway of introduction is during the delivery of humanitarian aid in the aftermath of natural disasters. [24] [25] This occurred during relief efforts for Hurricane Maria in Dominica, it was found that the common green iguana, the Cuban tree frog, and potentially the Venezuela snouted tree frog were introduced with the former two becoming established. [25]

Most accidentally or intentionally introduced species do not become invasive as the ones mentioned above. For instance, Some 179 coccinellid species have been introduced to the U.S. and Canada; about 27 of these non-native species have become established, and only a handful can be considered invasive, including the intentionally introduced Harmonia axyridis , multicolored Asian lady beetle. [26] However the small percentage of introduced species that become invasive can produce profound ecological changes. In North America Harmonia axyridis has become the most abundant lady beetle and probably accounts for more observations than all the native lady beetles put together. [27]

Introduced plants

The horse chestnut, Aesculus hippocastanum, native to Greece and the Balkan peninsula, has been introduced across most of Europe and parts of North America as an ornamental plant. Introduced to the United Kingdom in 1616, this neophyte species has become widely distributed across the country. Though non-native, its leaves attract insects which serve as a food source for populations of native birds. Horse-chestnut 800.jpg
The horse chestnut, Aesculus hippocastanum , native to Greece and the Balkan peninsula, has been introduced across most of Europe and parts of North America as an ornamental plant. Introduced to the United Kingdom in 1616, this neophyte species has become widely distributed across the country. Though non-native, its leaves attract insects which serve as a food source for populations of native birds.

Many non-native plants have been introduced into new territories, initially as either ornamental plants or for erosion control, stock feed, or forestry. Whether an exotic will become an invasive species is seldom understood in the beginning, and many non-native ornamentals languish in the trade for years before suddenly naturalizing and becoming invasive.

Peaches, for example, originated in China, and have been carried to much of the populated world. Tomatoes are native to the Andes. Squash (pumpkins), maize (corn), and tobacco are native to the Americas, but were introduced to the Old World. Many introduced species require continued human intervention to survive in the new environment. Others may become feral, but do not seriously compete with natives, but simply increase the biodiversity of the area. One example would be Dandelions in North America, which have become an essential source of early season nectar for both native and introduced pollinators, and do not meaningfully compete with native grasses or flowers.

A very troublesome marine species in southern Europe is the seaweed Caulerpa taxifolia . Caulerpa was first observed in the Mediterranean Sea in 1984, off the coast of Monaco. By 1997, it had covered some 50 km2. It has a strong potential to overgrow natural biotopes, and represents a major risk for sublittoral ecosystems. The origin of the alga in the Mediterranean was thought to be either as a migration through the Suez Canal from the Red Sea, or as an accidental introduction from an aquarium. Another troublesome plant species is the terrestrial plant Phyla canescens, which was intentionally introduced into many countries in North America, Europe, and Africa as an ornamental plant. [30] [31] This species has become invasive in Australia, where it threatens native rare plants and causes erosion and soil slumping around river banks. [32] It has also become invasive in France where it has been listed as an invasive plant species of concern in the Mediterranean region, where it can form monocultures that threaten critical conservation habitats. [33]

Japanese knotweed grows profusely in many nations. Human beings introduced it into many places in the 19th century. It is a source of resveratrol, a dietary supplement. It can grow in building foundations, threatening their stability, and spreads quite quickly.

Introduced animals

Chickens Gallus gallus domesticus, from Asia, introduced in the rest of the world Braekel.jpg
Chickens Gallus gallus domesticus , from Asia, introduced in the rest of the world

Most introduced species do not become invasive. Examples of introduced animals that have become invasive include the gypsy moth in eastern North America, the zebra mussel and alewife in the Great Lakes, the Canada goose and gray squirrel in Europe, the beaver in Tierra del Fuego, the muskrat in Europe and Asia, the cane toad and red fox in Australia, nutria in North America, Eurasia, and Africa, and the common brushtail possum in New Zealand. In Taiwan, the success of introduced bird species was related to their native range size and body size; larger species with larger native range sizes were found to have larger introduced range sizes. [34]

One notoriously devastating introduced species is the small Indian mongoose ( Urva auropunctata ). Originating in a region encompassing Iran and India, it was introduced to the West Indies and Hawaii in the late 1800s for pest control. Since then, it has thrived on prey unequipped to deal with its speed, nearly leading to the local extinction of a variety of species. [35]

In some cases, introduced animals may unintentionally promote the cause of rewilding. [36] For example, escaped horses and donkeys that have gone feral in the Americas may play ecological roles similar to those of the equids that became extinct there at the end of the Pleistocene. [37]

Most commonly introduced species

Some species, such as the Western honey bee, brown rat, house sparrow, ring-necked pheasant, and European starling, have been introduced very widely. In addition there are some agricultural and pet species that frequently become feral; these include rabbits, dogs, ducks, snakes, goats, fish, pigs, and cats.


When a new species is introduced, the species could potentially breed with members of native species, producing hybrids. The effect of the creating of hybrids can range from having little effect, a negative effect, to having devastating effects on native species. Potential negative effects include hybrids that are less fit for their environment resulting in a population decrease. This was seen in the Atlantic Salmon population when high levels of escape from Atlantic Salmon farms into the wild populations resulted in hybrids that had reduced survival. [38] Potential positive effects include adding to the genetic diversity of the population which can increase the adaptation ability of the population and increase the number of healthy individuals within a population. This was seen in the introduction of guppies in Trinidad to encourage population growth and introduce new alleles into the population. The results of this introduction included increased levels of heterozygosity and a larger population size. [39] Wide-spread introductions of non-native iguanas are causing devastating effects on native Iguana populations in the Caribbean Lesser Antilles, as hybrids appear to have higher fitness than native iguanas, leading to competitive outcompetition and replacement. [40] [41] Numerous populations have already become extinct and hybridization continues to reduce the number of native iguanas on multiple islands.

On a planetary body

It has been hypothesized that invasive species of microbial life could contaminate a planetary body after the former is introduced by a space probe or spacecraft, either deliberately or unintentionally. [42] It has also been hypothesized that the origin of life on earth is due to introductions of life from other planets billions of years ago, possibly by a sentient race. Projects have been proposed to introduce life to other lifeless but habitable planets in other star systems some time in the future. In preparation for this, projects have been proposed to see if anything is still alive from any of the feces left behind during the moon landings in the 1960s. [43]

See also

Related Research Articles

Invasive species Non-native organism causing ecological, environmental, and/or economic damage

An invasive species is an introduced organism that becomes overpopulated and harms its new environment. Although most introduced species are neutral or beneficial with respect to other species, invasive species adversely affect habitats and bioregions, causing ecological, environmental, and/or economic damage. The term can also be used for native species that become harmful to their native environment after human alterations to its food web – for example the purple sea urchin which has decimated kelp forests along the northern California coast due to overharvesting of its natural predator, the California sea otter. Since the 20th century, invasive species have become a serious economic, social, and environmental threat.

Feral Wild-living but normally domestic animal or plant

A feral animal or plant is one that lives in the wild but is descended from domesticated individuals. As with an introduced species, the introduction of feral animals or plants to non-native regions may disrupt ecosystems and has, in some cases, contributed to extinction of indigenous species. The removal of feral species is a major focus of island restoration.

Gene flow Transfer of genetic variation from one population to another

In population genetics, gene flow is the transfer of genetic material from one population to another. If the rate of gene flow is high enough, then two populations will have equivalent allele frequencies and therefore can be considered a single effective population. It has been shown that it takes only "one migrant per generation" to prevent populations from diverging due to drift. Populations can diverge due to selection even when they are exchanging alleles, if the selection pressure is strong enough. Gene flow is an important mechanism for transferring genetic diversity among populations. Migrants change the distribution of genetic diversity among populations, by modifying allele frequencies. High rates of gene flow can reduce the genetic differentiation between the two groups, increasing homogeneity. For this reason, gene flow has been thought to constrain speciation and prevent range expansion by combining the gene pools of the groups, thus preventing the development of differences in genetic variation that would have led to differentiation and adaptation. In some cases dispersal resulting in gene flow may also result in the addition of novel genetic variants under positive selection to the gene pool of a species or population

Naturalisation is the ecological phenomenon through which a species, taxon, or population of exotic origin integrates into a given ecosystem, becoming capable of reproducing and growing in it, and proceeds to disseminate spontaneously. In some instances, the presence of a species in a given ecosystem is so ancient that it cannot be presupposed whether it is native or introduced.

The need for a clearly defined and consistent invasion biology terminology has been acknowledged by many sources. Invasive species, or invasive exotics, is a nomenclature term and categorization phrase used for flora and fauna, and for specific restoration-preservation processes in native habitats. Invasion biology is the study of these organisms and the processes of species invasion.

Ecologically, invader potential is the qualitative and quantitative measures of a given invasive species probability to invade a given ecosystem. This is often seen through climate matching. There are many reasons why a species may invade a new area. The term invader potential may also be interchangeable with invasiveness. Invader potential is a large threat to global biodiversity. It has been shown that there is an ecosystem function loss due to the introduction of species in areas they are not native to.

Species translocation

Translocation in wildlife conservation is the capture, transport and release or introduction of species, habitats or other ecological material from one location to another. It contrasts with reintroduction, a term which is generally used to denote the introduction into the wild of species from captive stock.

Grasses are one of the most abundant floras on all continents, except Antarctica. Their divergence is estimated to have taken place 200 million years ago. Humans have intentionally and unintentionally introduced these species to North America through travel and trade. On the North American plains, prairies, grasslands, and meadows at least 11% of grasses are non-native. North America is considered a hotspot for many invasive species of grasses, which threatens all of the endangered native grass species and potentially threatens other grass species. Conservation tactics and management policies can help prevent invasive species from taking over and driving native North American plants to extinction.

Genetic pollution Term for uncontrolled gene flow into wild populations

Genetic pollution is a controversial term for uncontrolled gene flow into wild populations. It is defined as "the dispersal of contaminated altered genes from genetically engineered organisms to natural organisms, esp. by cross-pollination", but has come to be used in some broader ways. It is related to the population genetics concept of gene flow, and genetic rescue, which is genetic material intentionally introduced to increase the fitness of a population. It is called genetic pollution when it negatively impacts on the fitness of a population, such as through outbreeding depression and the introduction of unwanted phenotypes which can lead to extinction.

Agricultural pollution Type of pollution caused by agriculture

Agricultural pollution refers to biotic and abiotic byproducts of farming practices that result in contamination or degradation of the environment and surrounding ecosystems, and/or cause injury to humans and their economic interests. The pollution may come from a variety of sources, ranging from point source water pollution to more diffuse, landscape-level causes, also known as non-point source pollution and air pollution. Once in the environment these pollutants can have both direct effects in surrounding ecosystems, i.e. killing local wildlife or contaminating drinking water, and downstream effects such as dead zones caused by agricultural runoff is concentrated in large water bodies.

Dispersal vector

A dispersal vector is an agent of biological dispersal that moves a dispersal unit, or organism, away from its birth population to another location or population in which the individual will reproduce. These dispersal units can range from pollen to seeds to fungi to entire organisms.

Island ecology is the study of island organisms and their interactions with each other and the environment. Islands account for nearly 1/6 of earth’s total land area, yet the ecology of island ecosystems is vastly different from that of mainland communities. Their isolation and high availability of empty niches lead to increased speciation. As a result, island ecosystems comprise 30% of the world’s biodiversity hotspots, 50% of marine tropical diversity, and some of the most unusual and rare species. Many species still remain unknown.

Neophyte (botany) Non-native plant species introduced in recent history

In botany, a neophyte is a plant species which is not native to a geographical region and was introduced in recent history. Non-native plants that are long-established in an area are called archaeophytes. In Britain, neophytes are defined more specifically as plant species that were introduced after 1492, when Christopher Columbus arrived in the New World and the Columbian Exchange began.

Green iguana Species of reptile

The green iguana, also known as the American iguana or the common green iguana, is a large, arboreal, mostly herbivorous species of lizard of the genus Iguana. Usually, this animal is simply called the iguana. The green iguana ranges over a large geographic area; it is native from southern Brazil and Paraguay as far north as Mexico, and has been introduced from South America to Puerto Rico and is very common throughout the island, where it is colloquially known as gallina de palo and considered an invasive species; in the United States, feral populations also exist in South Florida, Hawaii, the U.S. Virgin Islands and the Rio Grande Valley of Texas. Green iguanas have also successfully colonised the island of Anguilla, arriving on the island in 1995 after rafting across the Caribbean from Guadeloupe, where they were introduced.

Gene drive Way to propagate genes throughout a population

A gene drive is a natural process and technology of genetic engineering that propagates a particular suite of genes throughout a population by altering the probability that a specific allele will be transmitted to offspring. Gene drives can arise through a variety of mechanisms. They have been proposed to provide an effective means of genetically modifying specific populations and entire species.

Climate change and invasive species

Climate change and invasive species is the destabilization of the environment caused by climate change that is facilitating the spread of invasive species.

In biology, overabundant species refers to an excessive number of individuals and occurs when the normal population density has been exceeded. Increase in animal populations is influenced by a variety of factors, some of which include habitat destruction or augmentation by human activity, the introduction of invasive species and the reintroduction of threatened species to protected reserves.

Invasion genetics

Invasion genetics is the area of study within biology that examines evolutionary processes in the context of biological invasions. Invasion genetics considers how genetic and demographic factors affect the success of a species introduced outside of its native range, and how the mechanisms of evolution, such as natural selection, mutation, and genetic drift, operate in these populations. Researchers exploring these questions draw upon theory and approaches from a range of biological disciplines, including population genetics, evolutionary ecology, population biology, and phylogeography.

Grateloupia turuturu, known as the devil's tongue weed, is a marine species of the Rhodophyta plant, a type of seaweed, native to eastern Asia and parts of eastern Russia. Due to global shipping and maritime activities, G. turuturu has become an invasive species that has altered natural communities by out-competing native seaweed species, this has resulted in a loss of habitat in many parts of the world, primarily in Australia, northern Ireland, Great Britain, and the northeastern United States. Other common names for this species are the "red menace" and "red tide".

Hemerochory Propagation of plants by "the culture"

Hemerochory is the distribution of cultivated plants or their seeds and cuttings, consciously or unconsciously, by humans into an area that they could not colonize through their natural mechanisms of spread, but are able to maintain themselves without specific human help in their new habitat.


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