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Assessing the influence of astronomical phenomena on terrestrial biodiversity

Assessing the influence of astronomical phenomena on terrestrial biodiversity. Fabo Feng, Coryn Bailer-Jones Max Planck Institute for Astronomy, Heidelberg 27.09.2012. Background. Rohde & Muller, Nature, 2005. Number of genera (thansands). Biodiversity = Origination – Extinction

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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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