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Qualitative differences between naïve and scientific
Qualitative differences between naïve and scientific

... Wrst formulated by Greek philosophers as early as the seventh century BC (Mayr, 1982), yet it remained unsolved until Darwin published The Origin of Species in 1859. Darwin’s solution was inspired by three empirical phenomena: (1) superfecundity, or the fact that organisms often produce more oVsprin ...
determination of food chain length using the hyperparasitoid gelis
determination of food chain length using the hyperparasitoid gelis

... by a combination of factors. Factors influencing food-chain length are: (i) Availability of food resources: resources should be adequate for development and survival of organisms in the next trophic level. However, Post (2002) claims that the availability of food resources that the ecosystem provide ...
Are there general laws in parasite community - MiVEGEC
Are there general laws in parasite community - MiVEGEC

... given host population. Then the highest level of parasite organization is the suprapopulation which represents all individuals of a given parasite species within an ecosystem. Next, the parasite compound community consists of all the parasite communities within an ecosystem (see Esch et al. 1990). T ...
smooth cordgrass Spartina alterniflora Loisel.
smooth cordgrass Spartina alterniflora Loisel.

... cordgrass can decrease water flow and cause flooding at the mouths of rivers. The establishment of Spartina species in mudflats will favor invertebrate species associated with salt marshes over those associated with unvegetated mudflats (Jacono 1998, Daehler 2000, WAPMS 2004). Biology and Invasive P ...
Bill Shape and Sexual Shape dimorphiSm Between two Archilochus
Bill Shape and Sexual Shape dimorphiSm Between two Archilochus

... dimorphism (SSD), and a number of mechanisms have been proposed to explain its variable distribution among taxa (Abouheif and Fairbairn 1997, Colwell 2000). Darwin (1871) proposed that sexual selection and selection for increased fecundity could be mechanisms that explain patterns of size dimorphism ...
Seagrass and Seagrass Beds
Seagrass and Seagrass Beds

... meadow are a single plant, connected underground by their roots in what’s known as a rhizome root system. In some seagrass species, a meadow can spring up from a single plant in less than a year; in slow-growing species, it can take hundreds of years. ...
Food web assembly rules
Food web assembly rules

... For consumer-resource relationships, the competitive exclusion principle states that when two consumers compete for the exact same resource within an environment, one consumer will eventually outcompete and displace the other [4, 5]. It is known that the number of coexisting species cannot exceed th ...
Decoys in Predation and Parasitism
Decoys in Predation and Parasitism

... (Pius and Leberg 1998), or information parasitism, where a species may benefit from the alarm raised by others (Nuechterlein 1981), and the decoy effect (Christensen et al. 1976; Vos et al. 2001; Wilkinson, 2001), which itself can take a variety of forms. In its simplest form, the third species, whi ...
Inter- and intraspecific parasitism
Inter- and intraspecific parasitism

... Interspecific parasitism: definition Parasite (pathogen) = organism that obtains its nutrients from one or a very few host individuals, causing harm* but not causing host death immediately. Parasitoid = egg to larval organism that obtains its nutrients from a single host individual, causing host dea ...
Inter- and intraspecific parasitism interactions
Inter- and intraspecific parasitism interactions

... Interspecific parasitism: definition Parasite (pathogen) = organism that obtains its nutrients from one or a very few host individuals, causing harm* but not causing host death immediately. Parasitoid = egg to larval organism that obtains its nutrients from a single host individual, causing host dea ...
Emergence and maintenance of biodiversity in an evolutionary food
Emergence and maintenance of biodiversity in an evolutionary food

... the infrequent immigration of new species from a pre-determined species pool. Such models can adequately describe how smaller food webs, for example on islands, originate through the immigration of species from a mainland, but do not in general provide an adequate description of the origin of food w ...
Enemy-free space via host plant chemistry and dispersion
Enemy-free space via host plant chemistry and dispersion

... readily attack generalist herbivores, and (3) suffer a reduction in fitness when they have a diet of prey containing detrimental plant chemicals. Evidence for these ideas would provide circumstantial support for the Bernays and Graham (1988) view that predation is an important selective force for fe ...
Pygmy Slow Loris
Pygmy Slow Loris

... The Mysore slender loris does not require a sleeping box, but instead would benefit greatly from a dense stand of bamboo. They will naturally seek shelter between the bamboo stands. Their enclosures must include a complex climbing structure with vertical, horizontal and diagonal angles. They are ada ...
The scope of the problem - Assets
The scope of the problem - Assets

... their partners are multilevel issues we finally focus on a hierarchical perspective integrating key points from the life-history level to applied problems at the ecosystem level, including the invasion of exotic species of ants and their subsequent effects on community structure (Chapter 7). We end ...
PlantCompDefNotes05
PlantCompDefNotes05

... by separating organisms in space and time. An example of this is resource partitioning. ...
Assessing ecological specialization of an ant–seed dispersal
Assessing ecological specialization of an ant–seed dispersal

... the ecological structure and evolution of plant–animal mutualisms. Most plant–animal mutualisms are facultative and strongly asymmetric. In particular, myrmecochory (seed dispersal by ants) has been regarded as a very generalized interaction. Although some recent studies have suggested that only a f ...
Food web structure of three guilds of natural enemies: predators
Food web structure of three guilds of natural enemies: predators

... we assumed that the volume of food eaten is proportional to metabolic rate, and that this scales with the 3/4 power of body size, the most common though not the only reported relationship (reviewed in Glazier 2005). Thus in the predator food webs the aphids are scaled by their volume, and the predat ...
Eaton Canyon - Jocha
Eaton Canyon - Jocha

... 16) Yucca pollination ecology is an example of a tight symbiosis called mutualism (a mutually beneficial symbiotic relationship in which each species depends on the other for survival.) With only one exception, yucca reproduction depends on moths (nocturnal insect similar to a butterfly), which deli ...
Non-random biodiversity loss underlies predictable increases in
Non-random biodiversity loss underlies predictable increases in

... search efficiency is altered [2,33]. Disease prevalence can also be affected by heterogeneity in the competence of host reservoirs for parasite transmission [32,34]. Taken together, this body of work points to the importance of host biodiversity for controlling disease spread via interspecific varia ...
Extinction order and altered community structure
Extinction order and altered community structure

... extinction proneness, low to high. A negative response–effect correlation (a2) could result in a saturating functional form (b2). For example, this could arise from rare species with small population size and correspondingly small functional contributions being the most extinction prone. A positive ...
A Three-Way Trade-Off Maintains Functional Diversity under
A Three-Way Trade-Off Maintains Functional Diversity under

... parameterized by these trade-offs to see whether they promote coexistence and/or constrain community trait structure to empirically plausible values. We use a compilation of phytoplankton functional traits to quantify variation across species in traits related to velocity, affinity, and storage stra ...
- University of East Anglia
- University of East Anglia

... 2003; McGill et al. 2006; Williams et al. 2010). Therefore, to support mechanistic ...
Life cycles - naturebob.com
Life cycles - naturebob.com

... life of an insect. Insects—including aquatic insects—go through several transformations, often quite dramatic, during their lives. This process is called metamorphosis. All insects begin as eggs, where the insect embryo grows and develops, fueled by nutrients in the yolk. Eventually, the embryo is r ...
Seqential Predation: A Multi
Seqential Predation: A Multi

... The asymmetry in the two predator-prey relations is expressed explicitly in eqns (1): specific rate of predation on early prey depends only on predator density, whereas on late prey it depends on both predator and early prey density. Consequently, predator density has a different effect on each of t ...
galapagos research
galapagos research

... The specimen is frozen and available for future genetic testing to determine the species, although it is probable that all Geospizinae species are predated. Our study was conducted during a dry period at the start of the nesting season for terrestrial Galapagos birds and thus few nestlings would hav ...
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Coevolution



In biology, coevolution is ""the change of a biological object triggered by the change of a related object"". In other words, when changes in at least two species' genetic compositions reciprocally affect each other’s evolution, coevolution has occurred.There is evidence for coevolution at the level of populations and species. Charles Darwin briefly described the concept of coevolution in On the Origin of Species (1859) and developed it in detail in Fertilisation of Orchids (1862). It is likely that viruses and their hosts coevolve in various scenarios.However, there is little evidence of coevolution driving large-scale changes in Earth's history, since abiotic factors such as mass extinction and expansion into ecospaces seem to guide the shifts in the abundance of major groups. One proposed specific example was the evolution of high-crowned teeth in grazers when grasslands spread through North America - long held up as an example of coevolution. We now know that these events happened independently.Coevolution can occur at many biological levels: it can be as microscopic as correlated mutations between amino acids in a protein or as macroscopic as covarying traits between different species in an environment. Each party in a coevolutionary relationship exerts selective pressures on the other, thereby affecting each other's evolution. Coevolution of different species includes the evolution of a host species and its parasites (host–parasite coevolution), and examples of mutualism evolving through time. Evolution in response to abiotic factors, such as climate change, is not biological coevolution (since climate is not alive and does not undergo biological evolution).The general conclusion is that coevolution may be responsible for much of the genetic diversity seen in normal populations including: blood-plasma polymorphism, protein polymorphism, histocompatibility systems, etc.The parasite/host relationship probably drove the prevalence of sexual reproduction over the more efficient asexual reproduction. It seems that when a parasite infects a host, sexual reproduction affords a better chance of developing resistance (through variation in the next generation), giving sexual reproduction viability for fitness not seen in the asexual reproduction, which produces another generation of the organism susceptible to infection by the same parasite.Coevolution is primarily a biological concept, but researchers have applied it by analogy to fields such as computer science, sociology / international political economy and astronomy.
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