Testing hypotheses about tinkering in the fossil record: the case of the human skull

2004 ◽  
Vol 302B (3) ◽  
pp. 284-301 ◽  
Author(s):  
Daniel E. Lieberman ◽  
Gail E. Krovitz ◽  
Brandeis McBratney-Owen
Keyword(s):  
Fossil Record ◽  
Testing Hypotheses ◽  
Human Skull

scholarly journals Generating and testing hypotheses about the fossil record of insect herbivory with a theoretical ecospace

2021 ◽  
pp. 104564
Author(s):  
Sandra R. Schachat ◽  
Jonathan L. Payne ◽  
C. Kevin Boyce ◽  
Conrad C. Labandeira
Keyword(s):  
Fossil Record ◽  
Insect Herbivory ◽  
Testing Hypotheses

Likelihood tests of hypothesized durations: determining and accommodating biasing factors

Paleobiology ◽  
2000 ◽  
Vol 26 (3) ◽  
pp. 431-449 ◽  
Author(s):  
Peter J. Wagner
Keyword(s):  
Fossil Record ◽  
The Other ◽  
Data Sets ◽  
Time Sampling ◽  
Empirical Testing ◽  
Testing Hypotheses ◽  
Simplifying Assumptions ◽  
Extinction Events ◽  
Stratigraphic Range ◽  
Over Time

Paleobiologists frequently hypothesize that a taxon's duration (i.e., the true span from origination to extinction) exceeds its stratigraphic range (i.e., the span from first appearance to last appearance in the fossil record). One can test hypothesized duration by assessing the plausibility of the implicitly hypothesized gaps between origination and first appearance and / or between last appearance and extinction. Several tests assess the probability of not finding a taxon over some stratigraphic gap. Because the likelihood of a hypothesis given data reflects the probability of the data given that hypothesis, these probabilities also give the likelihood of a hypothesized duration. However, many probability / likelihood tests require simplifying assumptions about unknown sampling parameters such as the consistency of sampling over time, sampling intensities for unknown ancestors, and actual sampling intensities themselves.This paper examines the effects of sampling parameters on probability / likelihood tests and presents methods for testing hypotheses about these unknowns while testing hypotheses about true durations. Two data sets are used here as examples. One analysis tests the origination times among Paleozoic gastropods implied by phylogenetic inferences. The other analysis tests the extinction times among Maastrichtian ammonites implied by different numbers of extinction events. In both cases, hypotheses positing many gaps in the fossil record become more likely after accommodating uncertainty about sampling. However, the increased likelihoods are insufficient to prevent these hypotheses from being rejected in favor of hypotheses positing fewer gaps. In both cases, the conclusions are identical to those derived by simple methods using simple models for unknown sampling parameters. Although numerous factors can exaggerate the implausibility of gaps, making these factors parts of testable hypotheses is possible. Thus, excessive assumptions about sampling parameters need not hinder empirical testing of hypothesized durations.

scholarly journals A genome sequence from a modern human skull over 45,000 years old from Zlatý kůň in Czechia

2021 ◽  
Author(s):  
Kay Prüfer ◽  
Cosimo Posth ◽  
He Yu ◽  
Alexander Stoessel ◽  
Maria A. Spyrou ◽  
...  
Keyword(s):  
Middle East ◽  
Human Genome ◽  
Fossil Record ◽  
Modern Human ◽  
Upper Palaeolithic ◽  
Hunter Gatherers ◽  
Human Skull ◽  
A Genome ◽  
Out Of Africa ◽  
Genetic Makeup

AbstractModern humans expanded into Eurasia more than 40,000 years ago following their dispersal out of Africa. These Eurasians carried ~2–3% Neanderthal ancestry in their genomes, originating from admixture with Neanderthals that took place sometime between 50,000 and 60,000 years ago, probably in the Middle East. In Europe, the modern human expansion preceded the disappearance of Neanderthals from the fossil record by 3,000–5,000 years. The genetic makeup of the first Europeans who colonized the continent more than 40,000 years ago remains poorly understood since few specimens have been studied. Here, we analyse a genome generated from the skull of a female individual from Zlatý kůň, Czechia. We found that she belonged to a population that appears to have contributed genetically neither to later Europeans nor to Asians. Her genome carries ~3% Neanderthal ancestry, similar to those of other Upper Palaeolithic hunter-gatherers. However, the lengths of the Neanderthal segments are longer than those observed in the currently oldest modern human genome of the ~45,000-year-old Ust’-Ishim individual from Siberia, suggesting that this individual from Zlatý kůň is one of the earliest Eurasian inhabitants following the expansion out of Africa.

Testing hypotheses about ordinal interactions: Simulations and further comments.

1989 ◽  
Vol 74 (2) ◽  
pp. 247-252 ◽  
Author(s):  
Michael J. Strube ◽  
Philip Bobko
Keyword(s):  
Testing Hypotheses

Darwin's two competing phylogenetic trees: marsupials as ancestors or sister taxa?

2012 ◽  
Vol 39 (2) ◽  
pp. 217-233 ◽  
Author(s):  
J. David Archibald
Keyword(s):  
Fossil Record ◽  
Evolutionary Biology ◽  
Phylogenetic Trees ◽  
Charles Darwin ◽  
The Other ◽  
Charles Lyell ◽  
Single Origin ◽  
Molecular Studies ◽  
Richard Owen ◽  
First Time

Studies of the origin and diversification of major groups of plants and animals are contentious topics in current evolutionary biology. This includes the study of the timing and relationships of the two major clades of extant mammals – marsupials and placentals. Molecular studies concerned with marsupial and placental origin and diversification can be at odds with the fossil record. Such studies are, however, not a recent phenomenon. Over 150 years ago Charles Darwin weighed two alternative views on the origin of marsupials and placentals. Less than a year after the publication of On the origin of species, Darwin outlined these in a letter to Charles Lyell dated 23 September 1860. The letter concluded with two competing phylogenetic diagrams. One showed marsupials as ancestral to both living marsupials and placentals, whereas the other showed a non-marsupial, non-placental as being ancestral to both living marsupials and placentals. These two diagrams are published here for the first time. These are the only such competing phylogenetic diagrams that Darwin is known to have produced. In addition to examining the question of mammalian origins in this letter and in other manuscript notes discussed here, Darwin confronted the broader issue as to whether major groups of animals had a single origin (monophyly) or were the result of “continuous creation” as advocated for some groups by Richard Owen. Charles Lyell had held similar views to those of Owen, but it is clear from correspondence with Darwin that he was beginning to accept the idea of monophyly of major groups.

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