Late Cretaceous Amber Deposits from Saskatchewan, Canada

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Amber or fossilized resin offers palaeontologists one of the most detailed glimpses of ancient terrestrial ecosystems. In western Canada, amber deposits are found associated with coal seams, in dinosaur bonebeds, and in the remains of ancient river systems throughout the Late Cretaceous. This amber is typically too small and fragile for jewelry, but it captures insects and small fragments of larger animals (such as feathers), preserving these inclusions and their soft tissues in 3D with microscopic detail. The surrounding amber also retains some of its original chemistry and stable isotopic composition, allowing researchers to identify the group of trees that produced the deposit, and the conditions that they were living under. The goal of the proposed research is to intensively sample the Late Cretaceous rocks of western Canada for amber, analyzing this material and its inclusions, and placing them in the larger context of palaeoecology and insect evolution. The insect inclusions that are found will help to fill in a 20-million-year gap in the fossil record of insects that exists in the Late Cretaceous, thus improving our understanding of insect diversification and extinction around the end-Cretaceous extinction event. The amber will also provide data about the ancient forests and habitat conditions that existed at the time. Together, these aspects of the research will improve our understanding of terrestrial conditions during the Late Cretaceous, and the habitats occupied by dinosaurs. The outcomes of this work will be of interest to a broad range of scientists, including palaeontologists, evolutionary biologists and geologists, but will also have implications for researchers working on modern insects. Modern insect faunas are dominated by four hyper-diverse insect orders that grew in diversity alongside the rise of flowering plants, in the Cretaceous. These insect groups (beetles, flies, true bugs, plus the order containing ants, wasps, and bees) are major contributors to terrestrial ecosystems, and have significant ecological and economic importance, yet our understanding of their evolutionary relationships and responses to past events is limited by their fossil record. The proposed research will shed light on a key time interval for these insect groups, and provide a comparison point for the fossil record after the extinction event.