Pollen record of the Late Pleistocene-Holocene stratigraphic sequence and current plant biodiversity from Grotta Mora Cavorso (Simbruini Mountains, Central Italy).

Grotta Mora Cavorso (Jenne, Latium), a complex karstic system in Central Italy, has returned one of the most precious Prehistoric palaeontological and anthropological heritage. Through the analysis of pollen spectra and charcoals from cave stratigraphic levels (Late Pleistocene final phases-Holocene), the overall vegetation trend of the site was pointed out. Although taphonomy and palynology of cave deposits are complex, pollen assemblage represents a reliable source for inferring past vegetation; indeed, climatic, environmental, and cultural interactions determine fossil pollen record. Site formation processes and postdepositional bias should be generally considered in the analysis of stratigraphic sequences used to define paleoenvironmental conditions. The sediment deposits from Grotta Mora Cavorso showed a vegetation pattern point in out a progressive increase in woody plants from lower levels upward. Palynological investigations highlighted a changing environment predominantly characterized by cooler and perhaps more humid conditions than today, with plant subalpine and marsh communities nearby the cave. The ecological requirements of the identified plant taxa supplied useful indications to reconstruct ancient and modern environments of the Simbruini Mounts and the Upper Aniene River valley. This scenario, in accordance with previous faunistic and carpological findings and palynological analyses from Latium, provided a further perspective on the vegetation history, biodiversity, and climate of an important crossroads between the Adriatic and the Tyrrhenian coasts.

Four climate change scenarios for Gypsophila bermejoi G. López (Caryophyllaceae) to address whether bioclimatic and soil suitability will overlap in the future.

Climate change has altered the global distribution of many species. Accordingly, we have assessed here the potential shift in the distribution of Gypsophila bermejoi G. López under distinct scenarios of future climate change, this being a species endemic to the Iberian Peninsula. For strict gypsophiles, climatic changes affecting their potential area of distribution could be critical if the new range is not overlapped with suitable soils. Thus, the narrow bioclimatic niche and the endemic nature of this plant could make this species particularly vulnerable to climate change. We used the Maximum Entropy (MaxEnt) method to study the potential distribution of this taxon under four different scenarios of climate change, pin-pointing relevant changes in the potential distribution of this plant and enabling possible future areas of refuge to be assessed. Such scenarios are defined according to four Representative Concentration Pathways (RCPs) [, which represent different trends in the concentration of atmospheric carbon dioxide. As a result, we predict notable changes in the potential distribution of G. bermejoi, and the overlap between soil and bioclimatic suitability would be affected. We also used a Principal Component Analysis (PCA) to model the bioclimatic niche of this species, comparing it with that of its parental taxa. The evolution of bioclimatic suitability was assessed at the current locations of G. bermejoi and as this plant is a strict gypsophile, we generated suitability maps for sites with gypsum soils. Ultimately, this study identifies relevant changes in the potential distribution of G. bermejoi under specific climatic scenarios, observing remarkable differences in the outcomes of the different climate change scenarios. Interestingly, in some scenarios the bioclimatic suitability of G. bermejoi will be enhanced at many locations and even in the worst scenario some possible refuge areas were identified. G. bermejoi behaves more like a hardy survivor than as early victim.

Sympatric and allopatric niche shift of endemic Gypsophila (Caryophyllaceae) taxa in the Iberian Peninsula.

Several species of the Gypsophila genus are endemic to the Iberian Peninsula, including gypsophytes of particular ecological, evolutionary and biochemical interest, and taxa that have undergone both sympatric and allopatric genetic differentiation. The niche shift among these taxa has been assessed using ecological niche modelling and ordination techniques, adopting a niche overlap approach to compare the similarity and equivalency of the ecological niches. We used the Maximum Entropy method to study the potential distribution of these taxa in different eras: the Last Glacial Maximum (LGM), the Mid Holocene and the current conditions. We present evidence of niche shift during the speciation of G. bermejoi, with a strong niche overlap between the parental taxa (G. struthium subsp. struthium and G. tomentosa), yet both overlap much more weakly with the hybrid species. This phenomenon may be explained by genetic and epigenetic interactions, and it has been described in other species. We also studied the sister subspecies G. struthium subsp. struthium and G. struthium subsp. hispanica, with mostly allopatric distributions and with the Iberian System mountain range acting as a geographical barrier. The Iberian System and other mountain ranges may have favored differences in the climatic conditions on either side of the mountain range, which is consistent with an incipient process of bioclimatic ecological speciation. These results seem to indicate that niche shift can occur over very different timespans. In the case of G. bermejoi, speciation may have produced significant niche shifting in one or two generations due to its alloploid nature. By contrast, G. struthium subsp. struthium and G. struthium subsp. hispanica seem to have undergone a more gradual process of allopatric genetic differentiation driven by bioclimatic factors. Both these processes are relatively recent and they will have been strongly influenced by the climate change at the end of LGM.