Seeking for the best conditions for fish fossil preservation in Las Hoyas Konservat-Lagerstätte using microbial mats.

Autor: Mollá, Salvador, Alcorlo, Paloma, Buscalioni, Angela D., López-Archilla, Ana Isabel
Předmět:
Zdroj: Historical Biology; Oct2024, Vol. 36 Issue 10, p2009-2018, 10p
Abstrakt: Actuotaphonomic experiments demonstrate how microbial mats prevent or delay destructive processes. The rate at which carcasses are covered is a key to their preservation. Because of the growth rate of microbial mats depends on environmental conditions, a set of experiments have been carried out emulating the Barremian environmental conditions, analysed for temperatures at 14°C and 26°C (cooler and warmer seasons respectively) and atmospheric pCO2 (1000 ppm). For this purpose, the microbial mats were grown in mesocosms within an environmental chamber. Variations in primary production were quantified by measuring changes in dissolved O2 concentration in the water. Zebrafish carcasses were laid on the mats, and their coverage rates were calculated from the daily surface area covered by the mat. The results showed that the fish was covered twice as fast at 26°C, in coincidence with the highest values for the gross primary production and community respiration of the microbial mats. Therefore, for these Barremian conditions, the early stages of carcasses preservation would take place most effectively during the warmer seasons as decomposing activity would release nutrients that would enhance, together with temperature, the growth of mats. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index