dorsal/arxiv
View SchemaA Simple Explanation for Taxon Abundance Patterns
| Authors | Johan Chu, Chris Adami |
|---|---|
| Categories | |
| ArXiv ID | physics/0002001 |
| URL | https://arxiv.org/abs/physics/0002001 |
| DOI | 10.1073/pnas.96.26.15017 |
| Journal | Proc. Nat. Acad. Sci. 96 (1999) 15017 |
Abstract
For taxonomic levels higher than species, the abundance distributions of number of subtaxa per taxon tend to approximate power laws, but often show strong deviationns from such a law. Previously, these deviations were attributed to finite-time effects in a continuous time branching process at the generic level. Instead, we describe here a simple discrete branching process which generates the observed distributions and find that the distribution's deviation from power-law form is not caused by disequilibration, but rather that it is time-independent and determined by the evolutionary properties of the taxa of interest. Our model predicts-with no free parameters-the rank-frequency distribution of number of families in fossil marine animal orders obtained from the fossil record. We find that near power-law distributions are statistically almost inevitable for taxa higher than species. The branching model also sheds light on species abundance patterns, as well as on links between evolutionary processes, self-organized criticality and fractals.
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"abstract": "For taxonomic levels higher than species, the abundance distributions of\nnumber of subtaxa per taxon tend to approximate power laws, but often show\nstrong deviationns from such a law. Previously, these deviations were\nattributed to finite-time effects in a continuous time branching process at the\ngeneric level. Instead, we describe here a simple discrete branching process\nwhich generates the observed distributions and find that the distribution\u0027s\ndeviation from power-law form is not caused by disequilibration, but rather\nthat it is time-independent and determined by the evolutionary properties of\nthe taxa of interest. Our model predicts-with no free parameters-the\nrank-frequency distribution of number of families in fossil marine animal\norders obtained from the fossil record. We find that near power-law\ndistributions are statistically almost inevitable for taxa higher than species.\nThe branching model also sheds light on species abundance patterns, as well as\non links between evolutionary processes, self-organized criticality and\nfractals.",
"arxiv_id": "physics/0002001",
"authors": [
"Johan Chu",
"Chris Adami"
],
"categories": [
"physics.bio-ph",
"nlin.AO",
"physics.data-an",
"q-bio.PE"
],
"doi": "10.1073/pnas.96.26.15017",
"journal_ref": "Proc. Nat. Acad. Sci. 96 (1999) 15017",
"title": "A Simple Explanation for Taxon Abundance Patterns",
"url": "https://arxiv.org/abs/physics/0002001"
},
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