Periodic Reporting for period 2 - AMBER (Dating fossils with molecules – innovative approach to determine the age of Baltic AMBER)
Reporting period: 2019-09-01 to 2020-08-31
The core idea of my project was to apply an innovative approach of precise dating for this very important fossil deposit by using DNA, the morphology of extinct and extant species within the framework of advanced Bayesian statistics. Information contained in DNA sequences together with the morphology of both extinct and extant taxa allowed for estimating phylogenetically the age of fossils from Baltic amber, and thus the amber itself. I used a dataset from my previous project as a basis and expanded it with fossils from Cenozoic deposits worldwide.
The main result of the project is developing a method for estimating the age of fossil deposits using a total-evidence phylogenetic approach. This new approach has been used to establish the age of Baltic amber deposits.
The knowledge of the age of the Baltic amber fossils could be of use in e.g. evolutionary biology, palaeoecology, biogeography, and palaeoclimatology. It gives us an insight into the ecosystems' response to the dynamic climate changes that took place in the Eocene and shaped out the recent biota.
Together with my supervisor and designated postdoc, we validated the method performance and reliability by running a series of designed simulations. Simulated datasets are extremely useful tools because they can characterize the expected performance of phylogenetic methods under idealized conditions to test and validate newly implemented methods. The simulation study was run to assess whether well-dated fossil samples can be used in combination with extant samples, to date fossil samples from a deposit of unknown age.
The main results obtained in the project are the phylogeny of the rove beetle subfamily Paederinae and the estimated dates for Baltic amber deposits. The results have been disseminated via scientific publications, two already published, six more in progress. They were also presented at the 2nd Palaeontological Virtual Congress.
The results of using a phylogenetic approach to date Baltic amber are highly promising and show the potential of applying this newly developed method to difficult fossil deposits. Knowing the age of Baltic amber is important for reconstructing evolutionary events in the Eocene, which was a time of drastic climatic changes analogues to the current global warming. Climate change is among the most important environmental issues in the recent world, and its impact on biodiversity and ecosystems is not only of scientific interest but also stands high in the scientific and political agenda of the modern world. Baltic amber fossils with known age could be used as a tool for reconstruction of the palaeoclimate and palaeoenvironment in the Eocene in Europe. It could help us to understand the current geographic distribution of different groups and their species composition, which in turn, could indicate how the past ecosystem was reacting to these events and recovering after global warming.