Implications For Dispersal Research Articles

Population Genetics of Ceratitis capitata in South Africa: Implications for Dispersal and Pest Management

The invasive Mediterranean fruit fly (medfly), Ceratitis capitata, is one of the major agricultural and economical pests globally. Understanding invasion risk and mitigation of medfly in agricultural landscapes requires knowledge of its population structure and dispersal patterns. Here, estimates of dispersal ability are provided in medfly from South Africa at three spatial scales using molecular approaches. Individuals were genotyped at 11 polymorphic microsatellite loci and a subset of individuals were also sequenced for the mitochondrial cytochrome oxidase subunit I gene. Our results show that South African medfly populations are generally characterized by high levels of genetic diversity and limited population differentiation at all spatial scales. This suggests high levels of gene flow among sampling locations. However, natural dispersal in C. capitata has been shown to rarely exceed 10 km. Therefore, documented levels of high gene flow in the present study, even between distant populations (>1600 km), are likely the result of human-mediated dispersal or at least some form of long-distance jump dispersal. These findings may have broad applicability to other global fruit production areas and have significant implications for ongoing pest management practices, such as the sterile insect technique.

Geographic expansion of hermatypic and ahermatypic corals in the Gulf of Mexico, and implications for dispersal and recruitment

The >3000 oil/gas platforms in the northern Gulf of Mexico (GOM) provide shallow hard-substratum in a soft-bottom dominated ecosystem. Excepting the Flower Garden Banks (FGB) and deeper mesophotic banks, no shallow hard substrate has been available offshore since the Holocene. Platforms have facilitated coral geographic expansion in this region. We determined the distribution, abundance, and species diversity patterns on 42 platforms in this region, at ≤37m depth, along four cross-shelf transects: 1) S-SE from Corpus Christi, Texas; 2) S from Lake Sabine, Texas; 3) S from Terrebonne Bay, Louisiana; and 4) S-SW from Mobile, Alabama. Nine hermatypic, two ahermatypic, and one hydrozoan coral were found: hermatypes—Madracis decactis, Diploria strigosa, Montastraea cavernosa, Porites astreoides, Madracis formosa, Colpophyllia natans, Stephanocoenia intercepta, Stephanocoenia michelinii, and Millepora alcicornis (Hydrozoa); ahermatypes—Tubastraea coccinea, Oculina diffusa, and Phyllangia americana. Pattern-seeking analyses identified four community types: one with no hermatypic corals (inner and mid-shelf); one high diversity set of platforms, dominated by abundant Madracis decactis, occurring with four other species per platform (outer shelf); and a third dominated by Madracis decactis, in low abundance, co-dominated by D. strigosa and Millepora alcicornis (outer shelf). Species diversity was highest around the Flower Garden Banks. Hermatypic density and D. strigosa (broadcaster) in particular, was maximum around the FGB, extending northwards. Madracis decactis (brooder) densities peaked at the shelf edge, off Terrebonne Bay, Louisiana. Montastraea cavernosa densities were bimodal, peaking near the FGB and east of the Mississippi River. The FGB appear to be the source of hermatypic corals for most platform populations. Differences between the distribution patterns of Madracis decactis and D. strigosa, Montastraea cavernosa, and O. diffusa suggest that the brooder effects longer recruitment distances by averaging larval dispersal over a broad range of hydrographic conditions throughout the year, while the broadcaster utilizes only one set of conditions over the same period. Averaging respective dispersal strategies over decades may have produced the observed disparate distribution patterns. Ahermatypic coral density exceeded hermatypic density by 10,000 fold, peaking south of Terrebonne Bay, Louisiana and Mobile, Alabama, due to T. coccinea. Ahermatypic diversity was highest off Matagorda Island, Texas, decreasing from west to east. Multi-variate pattern-seeking analysis (PATN) identified four ahermatypic community types: one dominated by O. diffusa and T. coccinea in low abundances (shelf-wide distribution); one characterized by the absence of ahermatypic corals (generally near-shore); one heavily dominated by T. coccinea, and also by O. diffusa in low abundances (mid-shelf to shelf edge); and one dominated by T. coccinea, co-dominated by both P. americana and O. diffusa in low abundances (shelf-edge). T. coccinea and P. americana appear to be derived from the southern GOM off Mexico or the Caribbean. Unlike shrinking coral populations in other parts of the world, corals have expanded their range substantially in the northern Gulf of Mexico, in areas previously devoid or near devoid of corals, facilitated by thousands of oil/gas platforms deployed for decades throughout the region. It is also possible that coral populations on these platforms may act as potential larval sources for the FGB in the event of a mass coral mortality there.

Fragment reattachment, reproductive status, and health indicators of the invasive colonial tunicate Didemnum vexillum with implications for dispersal

The invasive colonial tunicate Didemnum vexillum is now widespread in coastal and offshore waters of New England, USA. D. vexillum can inflict ecological and economic damage through biofouling and habitat modification. Natural and anthropogenic processes that fragment colonies of D. vexillum may be accelerating the spread of this invader. Reattachment success and fragment viability were confirmed in the laboratory after four weeks of suspension in experimental aquaria. The shape of suspended D. vexillum fragments progressed from flattened to globular spheres and then flattened again after reattachment to the substrate. Reproductive activity, confirmed by the presence of eggs and larvae, was observed for fragments suspended up to 3 weeks suggesting that D. vexillum is capable of reproducing while in a fragmented, suspended state. An index of colony health was used to monitor change in D. vexillum health while in suspension. Overall, colony health declined with time in suspension although colonies that appeared dead (black and gray in overall color) still contained a substantial number of healthy live zooids. These results suggest that activities that cause fragmentation can significantly facilitate the spread of D. vexillum. Coastal managers should consider reducing or eliminating, when practical, activities that return fragmented colonies of D. vexillum to the water. In-water cleaning of biofouling and dredging are likely expediting the spread of this invasive species unless biofouling can be contained and removed from the water.

Post-weaning social behaviour within mother–offspring groups of the bushveld gerbil, Gerbilliscus leucogaster: implications for dispersal

Social behaviour has been implicated in the natal dispersal of several small mammal species. We studied social interactions within groups of bushveld gerbil Gerbilliscus leucogaster mothers and their weaned offspring in captivity. We examined groups (n = 8) over several weeks to assess whether mothers and juveniles tolerate one another beyond weaning, and to investigate behavioural influences surrounding the onset of dispersal. Each group was placed in a series of interconnecting tanks, allowing juveniles free movement between tanks but restricting the movement of the mother. In two of the eight groups the mother produced a second litter during the study; mothers in these two groups appeared to be less tolerant of their first litter compared to mothers in the remaining groups. The remaining groups showed very high levels of tolerance throughout the study, both between mothers and their offspring, and between siblings. Juveniles began showing independence from the mother around weaning, but although independent behaviour increased with juvenile age, there was no clear breakdown of the mother–offspring bond. In nature, offspring probably disperse passively at around five to six weeks old if no subsequent litter is born. However, the high tolerance within these groups suggests that dispersal could be delayed under particular circumstances.

The Impact of Ocean Acidification on Reproduction, Early Development and Settlement of Marine Organisms

Predicting the impact of warming and acidifying on oceans on the early development life history stages of invertebrates although difficult, is essential in order to anticipate the severity and consequences of future climate change. This review summarises the current literature and meta-analyses on the early life-history stages of invertebrates including fertilisation, larval development and the implications for dispersal and settlement of populations. Although fertilisation appears robust to near future predictions of ocean acidification, larval development is much more vulnerable and across invertebrate groups, evidence indicates that the impacts may be severe. This is especially for those many marine organisms which start to calcify in their larval and/or juvenile stages. Species-specificity and variability in responses and current gaps in the literature are highlighted, including the need for studies to investigate the total effects of climate change including the synergistic impact of temperature, and the need for long-term multigenerational experiments to determine whether vulnerable invertebrate species have the capacity to adapt to elevations in atmospheric CO2 over the next century.

The spatial scale of density-dependent growth and implications for dispersal from nests in juvenile Atlantic salmon

By dispersing from localized aggregations of recruits, individuals may obtain energetic benefits due to reduced experienced density. However, this will depend on the spatial scale over which individuals compete. Here, we quantify this scale for juvenile Atlantic salmon (Salmo salar) following emergence and dispersal from nests. A single nest was placed in each of ten replicate streams during winter, and information on the individual positions (±1 m) and the body sizes of the resulting young-of-the-year (YOY) juveniles was obtained by sampling during the summer. In six of the ten streams, model comparisons suggested that individual body size was most closely related to the density within a mean distance of 11 m (range 2–26 m). A link between body size and density on such a restricted spatial scale suggests that dispersal from nests confers energetic benefits that can counterbalance any survival costs. For the four remaining streams, which had a high abundance of trout and older salmon cohorts, no single spatial scale could best describe the relation between YOY density and body size. Energetic benefits of dispersal associated with reduced local density therefore appear to depend on the abundance of competing cohorts or species, which have spatial distributions that are less predictable in terms of distance from nests. Thus, given a trade-off between costs and benefits associated with dispersal, and variation in benefits among environments, we predict an evolving and/or phenotypically plastic growth rate threshold which determines when an individual decides to disperse from areas of high local density.

Effect of yolk utilization on the specific gravity of chokka squid (Loligo reynaudii) paralarvae: implications for dispersal on the Agulhas Bank, South Africa

Abstract Martins, R. S., Roberts, M. J., Chang, N., Verley, P., Moloney, C. L., and Vidal, E. A. G. 2010. Effect of yolk utilization on the specific gravity of chokka squid (Loligo reynaudii) paralarvae: implications for dispersal on the Agulhas Bank, South Africa. – ICES Journal of Marine Science, 67: 1323–1335. Specific gravity is an important parameter in the dispersal of marine zooplankton, because the velocity of currents, and therefore the speed of transport, is usually greatest near the surface. For the South African chokka squid (Loligo reynaudii), recruitment is thought to be influenced by the successful transport of paralarvae from the spawning grounds to a food-rich feature known as the cold ridge some 100–200 km away. The role of paralarval specific gravity on such transport is investigated. Specific gravity ranged from 1.0373 to 1.0734 g cm−3 during the yolk-utilization phase, implying that paralarvae are always negatively buoyant, regardless of yolk content. The data were incorporated into a coupled individual-based model (IBM)—Regional Ocean Modelling System model. The output showed that dispersal was dominantly westward towards the cold ridge. Also, modelled paralarval vertical distribution suggested that hydrodynamic turbulence was an important factor in dispersal. The negative buoyancy of early chokka squid paralarvae may reduce the risk of paralarvae being advected off the eastern Agulhas Bank and into the open ocean, where food is less abundant, so specific gravity may be important in enhancing the survival and recruitment of chokka squid.

Implications of dispersal and life history strategies for the persistence of Linyphiid spider populations

Linyphiid spiders have evolved the ability to disperse long distances by a process known as ballooning. It has been hypothesized that ballooning may allow populations to persist in the highly disturbed agricultural areas that the spiders prefer. In this study, I develop a stochastic population model to explore how the propensity for this type of long distance dispersal influences long term population persistence in a heterogeneous landscape where catastrophic mortality events are common. Analysis of this model indicates that although some dispersal does indeed decrease the probability of extinction of the population, the frequency of dispersal is only important in certain extremes. Instead, both the mean population birth and death rates, and the landscape composition, are much more important in determining the probability of extinction than the dispersal process. Thus, in order to develop effective conservation strategies for these spiders, better understanding of life history processes should be prioritized over an understanding of dispersal strategies.

Spatiotemporal variability in recruitment around Iriomote Island, Ryukyu Archipelago, Japan: implications for dispersal of spawning corals

Spatiotemporal recruitment patterns of scleractinian corals were investigated around Iriomote Island, Ryukyu Archipelago, Japan, in relation to adult coral cover in 2005 and 2006. Although almost all corals were broadcasting spawners, the relationship between recruitment and adult coral cover differed among coral families (Acroporidae, Poritidae, and Pocilloporidae), likely due to differences in embryonic development time. For spawning pocilloporid corals, whose larvae develop relatively more rapidly, recruitment was higher at sites where adult coral cover was higher. In contrast, recruitment was not related to adult coral cover in acroporid and poritid corals, whose embryonic development times were relatively slow. Moreover, recruitment of acroporid corals varied between years, and recruitment was greater at leeward compared to windward reefs for a few days after spawning. These results suggest that embryonic development time and wind-driven surface currents affect larval dispersal and subsequent recruitment patterns at a local scale. Based on embryonic development time, some spawning corals are more likely to have higher rates of self-seeding than others. Our results predict that among spawning corals, local populations of acroporid and poritid corals, whose larvae potentially disperse over long distances and recruit in neighboring reefs, are more resilient to local disturbances than those of pocilloporid corals, whose recruitment relies upon local stock.

Survival dynamics of scleractinian coral larvae and implications for dispersal

Survival of pelagic marine larvae is an important determinant of dispersal potential. Despite this, few estimates of larval survival are available. For scleractinian corals, few studies of larval survival are long enough to provide accurate estimates of longevity. Moreover, changes in mortality rates during larval life, expected on theoretical grounds, have implications for the degree of connectivity among reefs and have not been quantified for any coral species. This study quantified the survival of larvae from five broadcast-spawning scleractinian corals (Acropora latistella, Favia pallida, Pectinia paeonia, Goniastrea aspera, and Montastraea magnistellata) to estimate larval longevity, and to test for changes in mortality rates as larvae age. Maximum lifespans ranged from 195 to 244 d. These longevities substantially exceed those documented previously for coral larvae that lack zooxanthellae, and they exceed predictions based on metabolic rates prevailing early in larval life. In addition, larval mortality rates exhibited strong patterns of variation throughout the larval stage. Three periods were identified in four species: high initial rates of mortality; followed by a low, approximately constant rate of mortality; and finally, progressively increasing mortality after approximately 100 d. The lifetimes observed in this study suggest that the potential for long-distance dispersal may be substantially greater than previously thought. Indeed, detection of increasing mortality rates late in life suggests that energy reserves do not reach critically low levels until approximately 100 d after spawning. Conversely, increased mortality rates early in life decrease the likelihood that larvae transported away from their natal reef will survive to reach nearby reefs, and thus decrease connectivity at regional scales. These results show how variation in larval survivorship with age may help to explain the seeming paradox of high genetic structure at metapopulation scales, coupled with the maintenance of extensive geographic ranges observed in many coral species.

Geographic variations in Helleborus foetidus elaiosome lipid composition: implications for dispersal by ants

Geographic variations in the correspondence between diaspore phenotypes and disperser behavior are thought to determine the evolution of plant-animal dispersal mutualisms. Helleborus foetidus is a widely distributed plant in Western Europe, which seeds bear a lipid rich elaiosome attracting ant dispersers. Laboratory cross-tests were conducted to check the correspondence between diaspore phenotypes and ant preference in two localities of the Iberian Peninsula, Caurel and Cazorla, separated by 750 km. Diaspores from Caurel were systematically preferred to those from Cazorla by Formica lugubris (the major disperser at Caurel), and Aphaenogatser iberica and Camponotus cruentatus (both major dispersers at Cazorla). Further bioassays conducted on A. iberica only showed that differences in elaiosome traits were sufficient to explain ant preference. Separation of the lipid fractions composing the elaiosome revealed that triglycerides, diglycerides and free fatty acids were all dominated by oleic acid. The elaiosomes from Caurel contained relatively more free oleic acid but were less concentrated in linoleyl-containing triglycerides, free palmitic acid and free linoleic acid than those from Cazorla. The three lipid fractions were attractive to ants but dummies soaked with the free fatty acids extracted from Caurel were preferred to those from Cazorla. Taken together, these results reinforce the idea that oleic acid is a major releaser of seed collection by ants and suggest that geographic variations in free fatty acid composition affect the probability of diaspore removal by ants which in turn potentially determine plant demography.

Salinity tolerance of larval Rapana venosa: implications for dispersal and establishment of an invading predatory gastropod on the North American Atlantic coast.

The lack of quantitative data on the environmental tolerances of the early life-history stages of invading species hinders estimation of their dispersal rates and establishment ranges in receptor environments. We present data on salinity tolerance for all stages of the ontogenetic larval development of the invading predatory gastropod Rapana venosa, and we propose that salinity tolerance is the dominant response controlling the potential dispersal (=invasion) range of the species into the estuaries of the Atlantic coast of the United States from the current invading epicenter in the southern Chesapeake Bay. All larval stages exhibit 48-h tolerance to salinities as low as 15 ppt with minimal mortality. Below this salinity, survival grades to lower values. Percentage survival of R. venosa veligers was significantly less at 7 ppt than at any other salinity. There were no differences in percentage survival at salinities greater than 16 ppt. We predict that the counterclockwise, gyre-like circulation within the Chesapeake Bay will initially distribute larvae northward along the western side of the DelMarVa peninsula, and eventually to the lower sections of all major subestuaries of the western shore of the Bay. Given the observed salinity tolerances and the potential for dispersal of planktonic larvae by coastal currents, establishment of this animal over a period of decades from Cape Cod to Cape Hatteras is a high probability.

Genetic population structure of the net‐winged midge, Elporia barnardi (Diptera: Blephariceridae) in streams of the south‐western Cape, South Africa: implications for dispersal

SUMMARY 1. The net‐winged midges (Diptera: Blephariceridae), with highly specific habitat requirements and specialised morphological adaptations, exhibit high habitat fidelity and a limited potential for dispersal. Given the longitudinal and hierarchical nature of lotic systems, along with the geological structure of catchment units, we hypothesise that populations of net‐winged midge should exhibit a high degree of population sub‐structuring.2. Sequence variation in the cytochrome c oxidase subunit I (COI) region of the mitochondrial DNA (mtDNA) was examined to determine patterns of genetic variation and infer historical and contemporary processes important in the genetic structuring of populations of Elporia barnardi. The DNA variation was examined at sites within streams, between streams in the same range, and between mountain ranges in the south‐western Cape of South Africa.3. Twenty‐five haplotypes, 641 bp in length, were identified from the 93 individuals sampled. A neighbour‐joining tree revealed two highly divergent clades (∼5%) corresponding to populations from the two mountain ranges. A number of monophyletic groups were identified within each clade, associated with individual catchment units.4. The distribution of genetic variation was examined using analysis of molecular variance (amova). This showed most of the variation to be distributed among the two ranges (∼80%), with a small percentage (∼15%) distributed among streams within each range. Similarly, variation among streams on Table Mountain was primarily distributed among catchment units (86%). A Mantel's test revealed a significant relationship between genetic differentiation and geographical distance, suggesting isolation by distance (P < 0.001).5. Levels of sequence divergence between the two major clades, representing the two mountain ranges, are comparable with those of some intra‐generic species comparisons. Vicariant events, such as the isolation of the Peninsula mountain chain and Table Mountain, may have been important in the evolution of what is now a highly endemic fauna.6. The monophyletic nature of the catchment units suggests that dispersal is confined to the stream environment and that mountain ridges provide effective physical barriers to dispersal of E. barnardi.

Aerodynamic diameter of conidia of Erynia neoaphidis and other entomophthoralean fungi

The aerodynamic diameter, da, of conidia produced in vivo and in vitro by the entomopathogenic fungus Erynia neoaphidis were estimated using an impaction method. The estimated values of da for conidia produced in vivo were smaller than those produced in vitro: in vivo the values of da for primary and secondary conidia were between 16 and 18 μm (equivalent fall speed, Vs, 0.8–1.0 cm s−1); for in vitro produced conidia da values were between 28 and 31 μm (Vs, 2.4–3 cm s−1). For conidia produced by field collected cadavers the value of da, was estimated to be similar to that for conidia produced in vivo in the laboratory. The aerodynamic diameter of primary conidia of Conidiobolus obscurus (strain X39) and Zoophthora radicans (strain NW250) produced in vivo were also measured using the same method. The values of da for these two species were 45 and 17 μm (Vs, 6.2 and 0.9 cm s−1) respectively. Implications for dispersal of E. neoaphidis are discussed. The physical diameters of the test spores were measured microscopically and compared with the aerodynamic diameters.

Gamete concentrations and timing and success of fertilization in a rocky shore seaweed

Whether sperm limitation or sperm competition occurs during fertilization in the sea has drawn increasing attention because of its importance in understanding population structure and recruitment. Inferences have been based upon both artificial and natural studies of in situ fertilization success, because natural gamete concentrations have been difficult to measure. Here, gamete con- centrations and the timing of fertilization were examined during the tidal cycle in the fucoid alga Fucus vesiculosus L. on the Maine coast at Pemaquid Point and in the Narraguagus River estuary. Gamete concentrations were assessed by collecting samples from the water column throughout the tidal cycle; sperm were identified by indirect immunofluorescence using a F. vesiculosus-selective monoclonal antibody raised against sperm from a Maine population of this species. Eggs were detected visually, and fertilization was assessed by the presence and position of a sperm pronucleus within the egg. Gamete release occurred only on calmer days (Pemaquid Point) or calmer periods of the tidal cycle (Narraguagus estuary), and sperm:egg ratios near the time of fertilization ranged from 10:1 to 70:1. Fertilization success was 100% in both locations. Nearly all eggs were fertilized within a 1 h interval of the 6 to 7 h long high tide, 2 to 3 h after algae were covered by seawater. Gamete release occurred at low tide after a prolonged period (3 wk) of stormy weather that inhibited gamete release during high tide; this has implications for dispersal and interspecific hybridization. Archival environmental data from the US National Oceanic and Atmospheric Administration (NOAA, 1982 to 2000) were used to predict the frequency of successful reproduction during high tide and the poten- tial for gamete release at low tide. These studies demonstrate that sperm are not limiting to fertiliza- tion in F. vesiculosus.

Behaviour of pelagic larvae of four coral-reef fish species in the ocean and an atoll lagoon

In-situ behaviour of settlement-stage larvae (10–30 mm) of four coral-reef fishes – Acanthurus triostegus, Chromis viridis, Neoniphon argenteus and Ptereleotris sp. – differed between lagoon and ocean at Rangiroa Atoll, Tuamotu Islands, French Polynesia. Divers released 130 larvae individually in midwater, and recorded larval swimming speed, depth and direction. All species swam faster than average currents, and C. viridis swam faster in the lagoon than in the ocean. Vertical distribution behaviour of all species differed between ocean and lagoon, generally by larvae swimming deeper in the ocean. Nearly all individual larvae swam directionally. Within a species, distribution of average bearings of individual larvae was not directional, nor did it differ between ocean and lagoon. Larvae detected predators 3–6 m away, and stopped or changed depth or direction to avoid them. We therefore reject the 'simplifying assumptions' that reef-fish larvae are passive or that their behaviour is independent of location. Behavioural flexibility of settlement-stage reef-fish larvae has implications for dispersal, retention and population connectivity. This constitutes the first report of larval reef-fish behaviour in the open ocean. However, in the ocean, many larvae descended rapidly below safe diving depth, and adult remoras interfered, making in-situ study of larval behaviour difficult.

Accretional History of the North and South China Blocks, and the Microcontinents Between them: Implications for Dispersion of Gondwanaland

Accretional History of the North and South China Blocks, and the Microcontinents Between them: Implications for Dispersion of Gondwanaland

Sepal and nut size ratio of fruits of Asian Dipterocarpaceae and its implications for dispersal

ABSTRACTThe relationship between sepal and nut size of fruits was studied in fruit of 394 species of Dipterocarpaceae in Malesia and Sri Lanka. The fruits of many dipterocarps have long twisted sepals which have a role as blades for dispersal by gyration. But long sepals decrease resource allocation to other parts, and increase the chance of fruit being trapped in the canopy. The frequency distribution of the ratio of sepal length to nut length was bimodal. The gyrationdispersed group with longer sepals comprised 74% of Dipterocarpaceae studied. The group with short sepal mainly comprised understorey trees, but there were a few emergents. In both groups, sepal areas were expressed as a power function of nut volumes'. Because fruit weight per sepal area increases with fruit size, larger fruits fall more quickly than smaller fruits, and sepals of the former can not serve so effectively as propeller blades. This is consistent with the fact that a few emergent trees with large nuts have short sepals and are not dispersed by gyration. Therefore, the re-evolution of short fruit sepals appears to have been mainly due to two reasons: reduction of tree height and enlargement of nut size.

Dispersal between and colonization of apple byMetaseiulus occidentalis andTyphlodromus pyri (Acarina: Phytoseiidae)

Adult femaleMetaseiulus occidentalis Nesbitt immigrated faster and at higher rates than didTyphlodromus pyri Scheuten to mini-orchards of young apple trees at 0, 10 and 100 m downwind from four apple orchards in the Hood River Valley, Oregon. Colonization of mini-orchards also was faster byM. occidentalis. Rates of emigration were similar between species as measured by movement into trees placed within, but not in contact with source orchard trees. Dispersal and colonization may be influenced by intrinsic physiological and morphological attributes, food habits, and responses to prey and habitat requirements. Implications of dispersal and colonization by these mites to biological control and pesticide resistance management are discussed.

The statistical-inference approach to generalized thermodynamics

The thermodynamic implications of dispersion in finite sample sizes or small thermodynamic systems are investigated within the normal approximation to the Gibbs distribution.