We derived presence-absence maps from the logistic suitability output from MAXENT using the 10th percentile training presence threshold, which predicts absent the 10% most extreme presence observations, as these may represent recording errors, ephemeral populations, migrants, or the presence of unusual microclimatic conditions within a cell (e.g., [63]).
Because pollinators must locate these ephemeral populations in a landscape that may be largely composed of other plant associations, out-crossing may not be prevalent.
Within the ephemeral populations, the number of plants in the population will vary in relation to the size of the burn and the distribution of the seed bank.
Ephemeral populations are produced by the germination of dormant seeds from long-lived seed banks which are stimulated to germinate by a combination of unidentified positive cues found in wood smoke and the removal of inhibitors leached from the unburned litter of the dominant vegetation.
The native annual tobacco, Nicotiana attenuata, is found primarily in large ephemeral populations (typically for less than 3 growing seasons) after fires in sagebrush and pinyon-juniper ecosystems and in small persistent populations (for many growing seasons) in isolated washes typically along roadsides throughout the Great Basin Desert of the SW USA.
In contrast to these island-based models, meta-population theory attempts to understand systems of evolutionarily ephemeral, genetically subdivided populations that persist through time via colonisation and migration from source populations [ 21- 23].
We observed that introgressive hybridization is likely a widespread but ephemeral phenomenon for populations in species rich faunas like Neotropical freshwater fishes, although its role in the adaptation and/or diversification of these fishes and other tropical lineages remains to be fully explored.
This is not surprising for populations inhabiting ephemeral habitats, or for high altitude populations that face extreme environmental conditions as these often do experience fluctuations in population size [ 45, 52].
For many amphibian species, particularly those that rely on ephemeral ponds for reproduction, population persistence can be dependent on landscape hydrology with years of suboptimal rainfall resulting in reproductive failure.
Despite the importance of colonization for populations in ephemeral and unique habitats with high endemism, the process has been poorly studied in chemosynthetic environments.
