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Assessing the influence of astronomical phenomena on terrestrial biodiversity

This study investigates the potential influence of astronomical phenomena on terrestrial biodiversity by analyzing data on genera extinction rates and stellar density. The study evaluates various claimed astronomical mechanisms and builds an orbit-based model to test their validity. The results suggest no evidence for periodicity in biodiversity data. Additional information can be found at astroimpacts.org.

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Assessing the influence of astronomical phenomena on terrestrial biodiversity

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  1. Assessing the influence of astronomical phenomena on terrestrial biodiversity Fabo Feng, Coryn Bailer-Jones Max Planck Institute for Astronomy, Heidelberg 27.09.2012

  2. Background Rohde & Muller, Nature, 2005 Number of genera (thansands) Biodiversity = Origination – Extinction Trend + Periodic Oscillation? Age(Myr)

  3. Claimed astronomical mechanisms Perturb Oort Cloud (possibly caused by the motion of the Sun) Cosmic Ray(Star formation, interstellar magnetic field) Supernova & GRB Reviewed in Bailer-Jones (2009)

  4. A possible connection between the solar environment and the biosphere Stellar density Study the solar motion Build an orbit-based model Reference models Test the model

  5. Data: time series & extinction rate Raup & Sepkoski, Science, 1982 Bambach, Annu. Rev. Earth Planet. Sci., 2006 Rohde & Muller, Nature, 2005 Alroy et. al., Science, 2008

  6. stellar density Solar motion Orbit-based model

  7. reference models Orbit-based model Bayesian inference data sets Likelihood = Integral of the normalized extinction rate over the normalized stellar density Evidence = Averaging likelihood over the parameter space (initial condition) Evidence ratio = Evidence1/Evidence2 Extinction Rate Stellar Density

  8. Reference Models: Periodic Probability of observing the extinction time given the parameters of Periodicmodel

  9. Reference Models: Random Probability of observing the extinction time given the parameters of Random model

  10. Reference Models: Uniform Probability of observing the extinction time given the parameters of Uniform model

  11. Likelihood for Orbit-based model Data: B18 Model: Orbit-based model

  12. Likelihood for Periodic model Data: B18 Model: Periodic model

  13. Evidence Ratio Data: B18 Model: Orbit-based model v.s. reference models

  14. Summary • Neither the Orbit-based model nor other reference models are favored over the uniform model • In particular, no evidence for periodicity in biodiversity data • Additional information: astroimpacts.org

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