venerdì 26 ottobre 2018

Detection of Lower Cretaceous fossil impressions of a marine tetrapod on Monte Conero (Central Italy)

https://www.sciencedirect.com/science/article/pii/S0195667118302015
Detection of Lower Cretaceous fossil impressions of a marine tetrapod on Monte Conero (Central Italy)

Luca Natali a ⧫,  Alessandro Blasetti b,  Giuseppe Crocetti b

Istituto Italiano di Paleontologia Umana, c/o Museo Civico di Zoologia, Via Ulisse Aldrovandi, 18, 00197 Rome, Italy
Sistema Museale - Museo delle Scienze dell'Università di Camerino, Via Gioco del Pallone, 5, 62032 Camerino, MC, Italy
Corresponding author
 
https://doi.org/10.1016/j.cretres.2018.09.014
 

Abstract

Inside the Conero Natural Park, in Central Italy, on the top layers of the Maiolica Formation belonging to the Umbria-Marche succession, we discovered 11 depressions identified as a fossil trackway in an area forbidden to the public for safety reasons. We collected data about their dimensional and morphological characteristics, together with photographic documentation and cast collection, in an area difficult to reach. This data, with the characteristic alternation and the almost straight line of the depressions, together with the nature of the sediment on which they were imprinted, lead us to believe that we have found imprints constituting a trackway generated on a deep seabed. Furthermore, the results of our studies allow us to hypothesize that the series of tracks may have been impressed by the fore-paddles of a Lower Cretaceous marine tetrapod, a reptile not yet identified. According to current knowledge, the examined tracks seem to be unique for this period and rare for the deep seabed paleoenvironment.
 

Keywords

Ichnofossils; Marine reptile;Tetrapod; Lower Cretaceous; Central Italy; Monte Conero

1. Introduction

This paper comes deals with the discovery, by the senior author L. Natali, of ichnofossils, interpretable as imprints impressed in deep sea sediments, within the Natural Park of Conero. Shortly after the discovery, Natali informed Dr. Stefano Finocchi, area inspector for the Superintendence of Archaeological Heritage of the Marche Region, by means of a detailed written scientific report that is included in this paper. The Science Museum of the University of Camerino, here represented by the co-authors A. Blasetti and G. Crocetti, was commissioned by the local Superintendent to take care of the geological study and laboratory analysis. The importance of this study stems from the fact that comparatively little is known of the deep seabed paleoenvironment in Italy and worldwide [...], while there is quite a lot of literature on swim tracks bottom walking on shallow waters by aquatic tetrapods such as fresh and marine water turtles and crocodiles [...]. [...]

Cretaceous Research:
https://www.sciencedirect.com/science/article/pii/S0195667118302015

ResearchGate:
https://www.researchgate.net/publication/327862489_Detection_of_Lower_Cretaceous_fossil_impressions_of_a_marine_tetrapod_on_Monte_Conero_Central_Italy

giovedì 18 ottobre 2018

Evidence of polygenic adaptation to high altitude from Tibetan and Sherpa genomes

















Un recente lavoro pubblicato su Genome Biology and Evolution, a cui ho dato un mio contributo quale socio Ex-Plora e IsIPU.

https://doi.org/10.1093/gbe/evy233

Abstract:
Although Tibetans and Sherpa present several physiological adjustments evolved to cope with selective pressures imposed by the high altitude environment, especially hypobaric hypoxia, few selective sweeps at a limited number of hypoxia related genes were confirmed by multiple genomic studies. Nevertheless, variants at these loci were found to be associated only with downregulation of the erythropoietic cascade, which represents an indirect aspect of the considered adaptive phenotype. Accordingly, the genetic basis of Tibetan/Sherpa adaptive traits remains to be fully elucidated, in part due to limitations of selection scans implemented so far and mostly relying on the hard sweep model.
In order to overcome this issue, we used whole genome sequence data and several selection statistics as input for gene network analyses aimed at testing for the occurrence of polygenic adaptation in these high-altitude Himalayan populations. Being able to detect also subtle genomic signatures ascribable to weak positive selection at multiple genes of the same functional subnetwork, this approach allowed us to infer adaptive evolution at loci individually showing small effect sizes, but belonging to highly interconnected biological pathways overall involved in angiogenetic processes.
Therefore, these findings pinpointed a series of selective events neglected so far, which likely contributed to the augmented tissue blood perfusion observed in Tibetans and Sherpa, thus uncovering the genetic determinants of a key biological mechanism that underlies their adaptation to high altitude.

Vedi anche qui: https://www.researchgate.net/publication/328360018_Evidence_of_polygenic_adaptation_to_high_altitude_from_Tibetan_and_Sherpa_genomes

domenica 7 ottobre 2018

Seminario-laboratorio: "Siro e le orme mesozoiche scoperte sul Monte Conero".


 

Camerino (MC), giovedì 18 ottobre 2018

In occasione della Settimana del Pianeta Terra, in programma da domenica 14 a domenica 21 ottobre 2018, l’Italia va alla scoperta delle Geoscienze. La finalità è quella di far appassionare i giovani alla scienza, alle geoscienze in particolare, e trasmettere l’entusiasmo per la ricerca e la scoperta scientifica.
A Camerino (MC), giovedì 18 ottobre, è in programma un seminario-laboratorio, rivolto principalmente agli studenti delle Scuole superiori, dal titolo “Siro e le orme mesozoiche scoperte sul Monte Conero”.
Siro è il nome che è stato scelto dagli autori della ricerca per questo antico e sconosciuto rettile marino, che ha lasciato impressa una "pista", scoperta recentemente, negli antichi sedimenti marini del Monte Conero risalenti a circa 110 milioni di anni fa, nell'attuale territorio di Sirolo.
Lo scopritore Luca Natali, archeologo maceratese, insieme al geologo Giuseppe Crocetti e al biologo Alessandro Blasetti, entrambi del Museo delle Scienze Unicam, esporranno la storia del rinvenimento e il relativo studio scientifico dai tre condotto e pubblicato sulla prestigiosa rivista internazionale Cretaceous Research.

Pubblicazione scientifica sul ritrovamento:
- Cretaceous Research: Detection of Lower Cretaceous fossil impressions of a marine tetrapod on Monte Conero (Central Italy)
- vedi anche in Research Gate.

Alcuni articoli di stampa locale:
- Cronache Maceratesi: Siro, il dinosauro del Conero «Una scoperta eccezionale e il bello inizia adesso»
- Cronache di Ancona: Siro, il dinosauro del Conero «Una scoperta eccezionale e il bello inizia adesso»
- Cronache Maceratesi: Rettile preistorico sul Conero: trovate 11 orme di 110 milioni di anni
- Vivere Camerino: Settimana del Pianeta Terra nel segno di Unicam