Adaptive zone, Petersen-type communities, geographical range and ecological niche. Report 1. Defnitions and relations of the concepts

AimTo explore the biogeographic patterns of exotic species in order to discriminate between hypotheses postulated to produce several biogeographic phenomena: the latitudinal gradient in species richness, the latitudinal gradient in species geographical range size (Rapoport’s rule), species geographical range boundaries and patterns of invasion in the tropics.LocationData were taken from North and South America, Europe, Asia, Africa and oceanic islands.MethodsThe latitudinal extents of the geographical range of exotic species were recorded to the nearest 1° of latitude from several published sources. Species richness was tabulated by recording the number of naturalized species present within 5° bands of latitude. Rapoport’s rule was calculated by averaging the latitudinal extent of all exotic species present within 5° bands. The low‐latitude boundaries of species’ native and naturalized ranges were compared with the nearest 1° of latitude. These comparisons on continents were contrasted with those on islands.ResultsWithin the tropics, few exotic species have become naturalized and those that are have established large geographical ranges. Outside of the tropics, exotic species of birds, mammals, fishes and plants demonstrate qualitatively similar latitudinal gradients in richness and geographical range size. They show the same patterns as native species, where richness is negatively correlated and range size positively correlated with latitude. Further, the geographical ranges of naturalized species on continents rarely extend to latitudes lower than those in their native ranges. On islands (where biotic pressure is reduced) exotic species are more frequently naturalized at latitudes lower than those in their native ranges.Main conclusionsHypotheses for the latitudinal gradient in species richness and geographical range size that are based on past glaciation events or differential rates of speciation between regions may not be necessary to explain these gradients, as exotic species are recent colonists and their patterns of distribution cannot have been directly affected by past glaciation events or differential rates of speciation between regions. Further, the low‐latitude boundary of species geographical ranges may be set by tolerance for biotic pressure.

Geographic variation in pollination ecology is poorly documented, if at all, in many plant-pollinator systems. Great insights could be gained into the abiotic and biotic factors which impact the evolution of floral properties and their potential to lead to speciation by doing so, as both can vary naturally over the geographic range of a plant species. We characterized the pollination ecology of the Andean tree Oreocallis grandiflora (Family: Proteaceae) at the northern and southern ends of its range in Ecuador and Peru in terms of flower morphology, nectar properties, pollinators and plant reproduction. We found significant divergence in the two populations in terms of style length and flower openness, nectar standing crop and secretion rate, and pollinator community. We did not find a significant difference in the length of the pollen presenter or in nectar sucrose concentration by weight (% Brix). The observed divergence in floral traits between the two study populations may be related to a combination of factors, including genetic drift and isolation by distance, distinctive suites of pollinators, or heterospecific pollen competition, which future studies should further investigate. This study demonstrates that pollination ecology can vary substantially across the geographic range of a species, with implications for delimiting species and subspecific taxa.

ABSTRACTAim To analyse the global patterns in species richness of Viperidae snakes through the deconstruction of richness into sets of species according to their distribution models, range size, body size and phylogenetic structure, and to test if environmental drivers explaining the geographical ranges of species are similar to those explaining richness patterns, something we called the extreme deconstruction principle.Location Global.Methods We generated a global dataset of 228 terrestrial viperid snakes, which included geographical ranges (mapped at 1° resolution, for a grid with 7331 cells world‐wide), body sizes and phylogenetic relationships among species. We used logistic regression (generalized linear model; GLM) to model species geographical ranges with five environmental predictors. Sets of species richness were also generated for large and small‐bodied species, for basal and derived species and for four classes of geographical range sizes. Richness patterns were also modelled against the five environmental variables through standard ordinary least squares (OLS) multiple regressions. These subsets are replications to test if environmental factors driving species geographical ranges can be directly associated with those explaining richness patterns.Results Around 48% of the total variance in viperid richness was explained by the environmental model, but richness sets revealed different patterns across the world. The similarity between OLS coefficients and the primacy of variables across species geographical range GLMs was equal to 0.645 when analysing all viperid snakes. Thus, in general, when an environmental predictor it is important to model species geographical ranges, this predictor is also important when modelling richness, so that the extreme deconstruction principle holds. However, replicating this correlation using subsets of species within different categories in body size, range size and phylogenetic structure gave more variable results, with correlations between GLM and OLS coefficients varying from –0.46 up to 0.83. Despite this, there is a relatively high correspondence (r = 0.73) between the similarity of GLM‐OLS coefficients andR2values of richness models, indicating that when richness is well explained by the environment, the relative importance of environmental drivers is similar in the richness OLS and its corresponding set of GLMs.Main conclusions The deconstruction of species richness based on macroecological traits revealed that, at least for range size and phylogenetic level, the causes underlying patterns in viperid richness differ for the various sets of species. On the other hand, our analyses of extreme deconstruction using GLM for species geographical range support the idea that, if environmental drivers determine the geographical distribution of species by establishing niche boundaries, it is expected, at least in theory, that the overlap among ranges (i.e. richness) will reveal similar effects of these environmental drivers. Richness patterns may be indeed viewed as macroecological consequences of population‐level processes acting on species geographical ranges.

The evolution of ecological specialization underlies plant endemism in the Atlantic Forest.

The association between heliconiine butterflies and Passion flower vines is composed of three or more subassociations, in which each Heliconius species group feeds on a different Passiflora subgenus. The relationships are consistent with the adaptive zone hypothesis of Ehrlich and Raven, which would suggest that (1) species of the subgenus Plectostemma proliferated as a result of chemical barriers to herbivory, which created a herbivore-free adaptive zone in which speciation and diversification took place, and (2) species of the H. erato-charitonia group overcame these barriers and entered a competitor-free adaptive zone, in which they proliferated and speciated with those plants as hosts. The hypothesis that plant secondary chemicals were responsible for creating such barriers to herbivory was tested using heliconiine species as bioassays, in which reduced growth rates indicated presence of chemical barriers to feeding. Contrary to expectation, plants of the subgenus Plectostemma showed little or no chemical defense against any species of heliconiine caterpillar. In contrast many plants of the "primitive" subgenus Granadilla possessed significant chemical barriers against herbivory by heliconiine larvae, excepting those species in the H. numata-melpomene species group. I concluded that chemical barriers to feeding were not responsible for proliferation and diversification in the subgenus Plectostemma, nor did chemicals create a competitor-free "adaptive zone" in which the H. erato-charitonia species-group could proliferate and speciate. Chemical barriers may have been important in the evolution of the subgenus Granadilla-heliconiine association. I suggest that plant allelochemics are only one of many possible barriers to herbivory which can help create "adaptive zones" for plants and their herbivores, and that the patterns of butterfly foodplant specialization discussed by Ehrlich and Raven (1964) are not necessarily the result of biochemical adaptation and counteradaptation.

Journal Article A MOLECULAR PHYLOGENETIC PERSPECTIVE ON THE ORIGINS OF A LOWLAND TROPICAL SALAMANDER FAUNA. II. PATTERNS OF MORPHOLOGICAL EVOLUTION Get access Allan Larson Allan Larson Department of Genetics and Museum of Vertebrate Zoology University of California Berkeley California 94720 Search for other works by this author on: Oxford Academic Google Scholar Evolution, Volume 37, Issue 6, 1 November 1983, Pages 1141–1153, https://doi.org/10.1111/j.1558-5646.1983.tb00228.x Published: 01 November 1983 Article history Received: 07 April 1982 Revision received: 31 January 1983 Published: 01 November 1983

The term “adaptive zone” appeared in paleontology and evolutionary biology, where it was not clearly defined, and gradually became obsolete and is now rarely used. This paper provides an updated definition of the term applicable in modern ecology and biogeography. It is shown that an adaptive zone is a particular case of Petersen-type communities. Sixteen implications were formulated that were theoretically derived from the facts known about range, Hutchinson’s niche, Petersen-type community, and their relationships with adaptive zone amended definition. The review includes the creation of simple and logical methods for finding, naming, and classifying adaptive zones. This regulates the conceptual apparatus of biology and opens up new lines of research in several of its branches. The applied aspects of the new adaptive zone concept are many current issues that include fisheries, aqua- and agriculture, forestry and hunting, natural nidality, combating alien species, weeds, pests and parasites, environmental protection, and artificial ecosystem creation. A Case Study is included that contains examples of maps of the adaptive zones of fauna from the far eastern seas and the northern part of the Pacific Ocean, which is one of the most important fishing regions in the world.

The trophic role assumed by an animal taxon in a community is best understood when the structure of the community is viewed in historical perspective (Whittaker 1977). In many environments it is not physical and behavioral limitations which guide a group's evolutionary potential, but the opportunity to exploit available adaptive zones, which, because of the nature of the fauna, were open (Hecht 1975, p. 248). [The term adaptive zone is used as defined by Van Valen (1971, p. 421) … “the niche of any taxon, especially a supraspecific one.” Van Valen distinguished adaptive zones from the “ways of life” of taxa. Adaptive zones are part of the environment and exist independently of taxa that exploit them.] It is often assumed or implied that a systematic group can, in its adaptive radiation, fill most of the available niches within a particular adaptive zone (Hecht 1975, p. 247). This type of “taxocene” analysis (Whittaker 1972, p. 218; Levandowsky and White 1977, p. 133), which promotes these views, has obvious shortcomings. It is now evident that mammals, for example, were unable to equally exploit and partition all available adaptive zones on every continent. The failure of carnivorous mammals to do this to a complete degree in Australia (see Hecht 1975, p. 247) and in South America (see Marshall 1977, p. 709) has some historical basis in the development of the stratification of the vertebrate fauna.

We draw on articles about adaptive leadership during a sustained crisis, 8 and on theories for promoting a growth mindset for leaders, faculty, and trainees At the individual level, adopting a growth mindset is important to prepare leaders, faculty, and trainees for ongoing work and future crises - Kurt Lewin 1 T he COVID-19 pandemic has changed individuals and health care institutions and is testing the graduate medical education (GME) community's collective adaptability and potential for growth under adversity and uncertainty Woodson Scott Jones, MD Ingrid Philibert, PhD, MA, MBA Lyuba Konopasek, MD Frederic W Hafferty, PhD There is nothing as practical as a good theory [Extracted from the article] Copyright of Journal of Graduate Medical Education is the property of Accreditation Council for Graduate Medical Education and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission However, users may print, download, or email articles for individual use This abstract may be abridged No warranty is given about the accuracy of the copy Users should refer to the original published version of the material for the full abstract (Copyright applies to all Abstracts )

With the increasing concern about species conservation, a need exists for quantitaive characterization of species’ geographic range and their borders. In this paper, we survey tools appropriate for the quantification of static spatial patterns related to geographical ranges and their borders. We then build on these static methods to consider the problem of changes in geographic range through time. Methods discussed are illustrated using lark sparrow data from the North American Breeding Bird Survey. While there is no such thing as the “best” or “only” method to analyze species geographical range and border, we show that a series of methods can be used in sequence to provide complementary and useful quantitative information for species occupancy of range. Indeed, the location of species’ borders estimated at different times can be compared to identify locations where species expand or go locally extinct. The ability to delineate accurately species’ ranges will be useful to conservation biologists, managers and ecologists.

A zoogeographic study of the Opisthobranchia (Mollusca, Gastropoda) from the Atlantic Ocean was carried out. Data on Opisthobranch occurrence were collated from literature records and databases. An estimated 1066 species were considered for this study, which belonged to the orders Cephalaspidea, Anaspidea, Sacoglossa, Notaspidea and Nudibranchia. Biogeographical patterns were analysed using cluster analysis (TWINSPAN) and ordination MDS (non-metric multidimensional scaling program). The richness of opisthobranchs increases from polar to tropical regions along Atlantic shores. The cluster analysis showed that there is a latitudinal and longitudinal separation of the biogeographical areas. The amphiatlantic species can be separated into four groups according to their distribution: G1.1.- the geographic range of species is limited to cold water on both sides of the Atlantic; G1.2.- species with geographic ranges limited to the western Arctic and Boreal regions, with a wide distribution in the eastern Atlantic, from the eastern Arctic or the eastern Boreal region to the Lusitanian and Mediterranean provinces; G2.1.- species with geographic ranges limited to the Caribbean and Mauritanian-Senegalese areas; G2.2.- species with a wide geographical distribution along both Atlantic shores.

Abstract: The species‐area relationship (SAR) has been used successfully to predict extinction from extent of habitat reduction. These extinction estimates assume that species have uniformly distributed range requirements and a minimum abundance level required for persistence; how many species are lost depends solely on how much habitat is removed, not on where it is removed. We consider another limiting case in which range requirements, rather than abundances, determine extinctions. We used a new method for constructing SARs based on assumptions about geographic ranges of species. Our results show that habitat destruction can change the SAR and consequently the number of species predicted to be lost due to habitat destruction. Our method generates SARs that vary in shape according to the specific distributions of geographic range and occupancy but that have the common feature of being described by a power law with an exponent of <1. When the geographic range of species was included in the SAR, the way habitat was lost became important. Although the SAR before habitat destruction is often used to predict species loss after habitat destruction, assumptions must be clearly stated. To predict the damage caused by habitat loss with our model, it is necessary to know the fraction of aggregated species, the distribution of geographic ranges, the form of habitat destruction, and the sampling protocol. The remaining theoretical challenge is to develop a full theory that links abundance and range.

AimIn order to better understand processes of speciation, range‐size transformation and extinction, macroecological studies seek to identify the evolutionary dynamics of species geographical ranges. This requires accurate estimates of range size and species age. Species ages are attainable through recent success with techniques to estimate phylogenetic divergence time. Conceptual synthesis of the inherent problems with these techniques has been limited. Our aim is to address the effects of estimation of phylogenetic divergence time on the relationship between species age and geographical range.InnovationCommonly, estimates of divergence time from the nodes of a time‐calibrated phylogeny are used as indicators of ages of extant species. However, this method can sometimes produce misleading age estimates, specifically in the presence of extinction and ancestral persistence. An example of this is illustrated using a comprehensive genetic dataset of genera with near‐complete sampling of species from four of the major coral reef fish families. We present a method to minimize the impacts of extinction and ancestral persistence on divergence time estimation. The method focuses on recent divergences and involves pairing minimum divergence time estimates (as indicators of species ages) with the minimum geographical range area between two sister‐species, for all sister‐species pairs.Main conclusionsWhen applied to coral reef fishes, this method revealed trends in the relationship between species age and geographical range. The difference in the trend recovered from excluding potential biases associated with ancestral persistence suggests that ancestral persistence may be prevalent among coral reef fishes, with successive peripheral speciation affecting area–age relationships. The method may reveal the occurrence of successive peripheral speciation events across a broad range of taxa.

We examined the relationship between pelagic larval duration (PLD)—a predictor of a species' dispersal potential—and the geographic distribution range of 62 Mediterranean littoral fishes. We found a significant, positive, weak relationship between PLD and distribution range. This relationship was observed in species with long PLDs that can cross the few dispersal barriers (Mac- aronesian Islands) present in the Mediterranean, and in endemic Mediterranean species with short PLDs. Species with inshore larvae exhibited a shorter PLD than species with offshore larvae. Species with larvae living in spring-summer had shorter PLDs than those developing in autumn-winter. Mean geographic range was clearly smaller for species with inshore larval distributions than for species with offshore larval distributions. However, the geographic range of species with benthic eggs was smaller than that of pelagic spawners. The size of the distribution range of fishes is probably not controlled only by the PLD. The inshore/offshore position and the season of planktonic life play an important role in ensuring the return of larvae to their settlement habitats. Consequently, these fac- tors also affect the size of the species' distribution range.

Many patterns of community structure will not be understood without reference to processes operating at regional and geographical scales (Cornell 1985a, b, Ricklefs 1987, Brown and Maurer 1989, Lawton 1990). This realization doubtless has been a prime motivation behind many recent studies of patterns in the sizes of species geographic ranges, and how these interact with such characteristics as local abundances, body sizes and trophic habits (Brown 1984, Brown and Maurer 1987, 1989, Bowers 1988, Gaston 1990, Gaston and Lawton 1990a, b, Pagel et al. 1991). It is thus somewhat curious to find that few of these studies explicitly state what they believe the size of a species geographic range, measured by whatever method, actually represents. This situation is made the more troublesome because different studies seem to be measuring different things. Thus, whilst Reaka (1980) quantifies species geographic ranges in terms of the numbers of degrees of latitude and longitude over which they have been recorded, and regards the numbers of 50 X 5? quadrats in which they were recorded as a measure of another aspect of their distribution, Schoener (1987) and Ford (1990) use numbers of occupied quadrats as a measure of geographic range size. This paper examines some of the ways in which the size of species geographic ranges could be measured, what these measures mean, and how they relate to one another.