Amber from El Soplao (Cantabria, Spain) is providing traces of brand-new insect types essential to understand how was life in Cretaceous forests. Credit: Xavier Delclòs, UB-IRBio
” The stories of plastic and fossil resins are very various, but they have something in typical: the curiosity associated with observing that some new and pertinent phenomenon emerged at some point in Earths history and was recorded in rocks”, states Delclòs, member of the Department of Earth and Ocean Dynamics and the Biodiversity Research Institute (IRBio) of the UB.
” Amber, and in specific its abundance, would be of little interest were it not for the truth that it contains in its interior many organisms that lived in the forests of the past, which have actually been completely preserved as fossils and which today permit us to understand the forests of the Cretaceous with a detail that seems unbelievable in some cases” says Enrique Peñalver, a member of the Geological and Mining Institute of Spain, a nationwide center of the Spanish National Research Council (CN IGME-CSIC) and also co-author of the study.
How were the big amber deposits formed?
The Cretaceous, a duration extending from 145.5 to 66 million years ago, represents a time of quick evolutionary modification and diversity of organisms. Today, the dominant conditions that in the Cretaceous enabled the mass formation of plentiful resin deposits all over the world are not present, nor is it known why there was, at the time of the dinosaurs, such an incredibly abundant production of resin.
” For about 54 million years, and for the very first time in Earths history, there was a mass production of resin by plants, and we still dont know why”, Delclòs and Peñalver explain. “Production amounts that could have formed fossil resin deposits of what we know today as amber had actually never ever been reached. From the Barremian to the Campanian, and thanks to the conditions existing on the planet, particular groups of conifers had the ability to stem big deposits of fossil resin that open a genuine window to the ecosystems of the past and today supply very important palaeobiological info. We have actually called this time span the Cretaceous Resinous Interval (CREI).”.
This research study intends to decipher development secrets about how the forest communities were 110 million years back. Credit: Xavier Delclòs, UB-IRBio.
The formation of large amber deposits needs the presence of trees with the capability to produce a great deal of resin. During the Cretaceous, only gymnosperms– e.g., conifers– which are evolutionarily older than flowering plants, might produce resin. Moreover, the resin had to be caught in a sedimentary environment without oxygen to preserve it for millions of years. However what ecological or biological aspects could have conditioned such resin production in the Cretaceous?
” Our study shows that, during the Cretaceous, coniferous forests were widely distributed across the world. These amber deposits formed during the CREI shared these attributes: high resin production specifically by conifers; the presence of fusain, a material stemmed from plant material burnt by forest fires; fossils protected in amber that correspond to comparable animals and flora amongst different deposits; and resin accumulation in transitional sedimentary environments under subtropical and temperate paleoclimates that accompany the beginning of sea-level increase phases.
The research study also suggests that the mass production of resin was not constant throughout the CREI nor was it equal everywhere: there were times of greater and lower production. In the study, brought out by a large multidisciplinary group of experts, the participation of Ricardo Pérez de la Fuente, from the Oxford University Museum (United Kingdom), is especially notable.
An open window to the disappeared world of the Cretaceous.
Pieces of amber recuperated by paleontologists in different websites around the globe offer brand-new insights into the Cretaceous. This duration saw the development of big terrestrial environments controlled by angiosperms– blooming plants– and a lot of the evolutionary lines of present-day organisms. The distribution of continents and ocean currents was altered, the environment was warmer and more damp than todays, and water level increased more than 200 meters above todays shorelines.
” In the environment, there were high levels of carbon dioxide (CO2) due to intense volcanism, but also of oxygen (O2) due to the great extension of forests to latitudes now covered by ice, a feature that likewise improves large-scale fires,” Delclòs and Peñalver note.
This is the international landscape and environment that controlled the Earth throughout much of the Cretaceous. The environmental factors conditioned the life and advancement of the organisms that existed on the world, especially the terrestrial ones, from the smallest to the great dinosaurs, and the relationships between the various species.
In this situation, the CREI emerges as an international phenomenon, with amber outcrops dispersed everywhere during the Cretaceous, and concentrated especially in Laurasia and the northern margin of Gondwana. Environmental elements may have impacted on an international scale, while biological elements– interaction in between plants and arthropods, etc– might have acted upon a regional scale.
” CREI represents an excellent window to a vanished world, at the starts of contemporary ecosystems controlled by flowering plants, where dinosaurs lived, and where the lineages of the first birds and mammals evolved. Studying this duration enables us to obtain many information of maximum clinical interest on phylogenetic relationships, extinct organisms, the beginning of habits that we can acknowledge today in many groups, intra- and interspecific relationships of extinct organisms (parasitism, pollination, parental care, swarming, forestry, recreation, etc) of the inhabitants of a terrestrial environment– the forest– that are not generally fossilized,” the specialists conclude.
Reference: “Amber and the Cretaceous Resinous Interval” by Xavier Delclòs, Enrique Peñalver, Eduardo Barrón, David Peris, David A. Grimaldi, Michael Holz, Conrad C. Labandeira, Erin E. Saupe, Christopher R. Scotese, Mónica M. Solórzano-Kraemer, Sergio Álvarez-Parra, Antonio Arillo, Dany Azar, Edwin A. Cadena, Jacopo Dal Corso, Jiří Kvaček, Antonio Monleón-Getino, André Nel, Daniel Peyrot, Carlos A. Bueno-Cebollada, Alejandro Gallardo, Beatriz González-Fernández, Marta Goula, Carlos Jaramillo, Iwona Kania-Kłosok, Rafael López-Del Valle, Rafael P. Lozano, Nieves Meléndez, César Menor-Salván, Constanza Peña-Kairath, Vincent Perricho, Ana Rodrigo, Alba Sánchez-García, Maxime Santer, Víctor Sarto i Monteys, Dieter Uhl, José Luis Viejo and Ricardo Pérez-de la Fuente, 25 June 2023, Earth-Science Reviews.DOI: 10.1016/ j.earscirev.2023.104486.
Pests protected in an amber piece from El Soplao in Cantabria (Spain). Credit: Xavier Delclòs, UB-IRBio
New research dives into the enigma of the mass production of resin throughout the Cretaceous duration, which led to the formation of amber. It highlights ambers significance in comprehending ancient environments and their organisms, and recommends that widespread coniferous forests and specific ecological conditions contributed to this phenomenon. The study highlights the Cretaceous periods value in understanding todays organisms and environments evolutionary origins.
What would a tourist from the future think if one day s/he could examine the rocks that are presently forming on the planet? Certainly, this person would discover quite a couple of plastic pieces and wonder why this product was so abundant in rocks of a particular age in the world. This is the same question that paleontologists and geologists have actually asked themselves after lots of years of studying another product: amber, the fossilized resin from the Cretaceous that assists us rebuild what the forests lived in by dinosaurs resembled.
We understand the factor for the abundance of numerous plastics in todays communities, “but we can just approximate the natural causes that would describe the production of big quantities of resin in the Cretaceous,” says Xavier Delclòs, professor at the Faculty of Earth Sciences of the University of Barcelona and first author of a short article published in the journal Earth-Science Reviews that addresses this enigma of modern-day paleontology.
New research study dives into the enigma of the mass production of resin during the Cretaceous duration, which led to the development of amber. “Production amounts that could have formed fossil resin deposits of what we know today as amber had actually never been reached. Throughout the Cretaceous, only gymnosperms– e.g., conifers– which are evolutionarily older than flowering plants, could produce resin. What biological or ecological elements could have conditioned such resin production in the Cretaceous?
Pieces of amber recovered by paleontologists in various sites around the world supply new insights into the Cretaceous.
