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Assessing the influence of astronomical phenomena on terrestrial biodiversityPowerPoint Presentation

Assessing the influence of astronomical phenomena on terrestrial biodiversity

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Assessing the influence of astronomical phenomena on terrestrial biodiversity

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Assessing the influence of astronomical phenomena on terrestrial biodiversity

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Fabo Feng, Coryn Bailer-Jones

Max Planck Institute for Astronomy, Heidelberg

27.09.2012

Rohde & Muller, Nature, 2005

Number of genera (thansands)

Biodiversity = Origination – Extinction

Trend + Periodic Oscillation?

Age(Myr)

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)

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

Raup & Sepkoski, Science, 1982

Bambach, Annu. Rev. Earth Planet. Sci., 2006

Rohde & Muller, Nature, 2005

Alroy et. al., Science, 2008

stellar density

Solar motion Orbit-based model

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

Probability of

observing the extinction time given

the parameters of Periodicmodel

Probability of

observing the

extinction time given

the parameters of Random model

Probability of

observing the

extinction time given

the parameters of Uniform model

Data: B18

Model: Orbit-based model

Data: B18

Model: Periodic model

Data: B18

Model: Orbit-based model v.s. reference models

- 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