In this article, Phillips has an
argument that transference errors are dependent on a mammal’s body size and
lifespans, causing a rise in previous estimates of interordinal divergence
times. He also suggests that the majority of interordinal divergences are
positioned after the KPg boundary. Although Phillips does believe in using the
explosive model to post the majority of interordinal diversification after the
KPg mass extinction, he also presented the idea that emersions of the Xenarthra,
Afrotheria, Euarchontoglires, and Laurasiatheria lineages came from the soft
explosive model. Assumptions were formed from using the explosive mode,
believing that extinctions were caused by both interordinal and intraordinal
diversification after the KPg mass, making morphological cladistic studies of
Cretaceous eutherians and crown Placentalia to become segregated from one
another.

                 In the methods section of this article, the
following things were calculated: number of lineages, number of new lineages,
and number of new lineages per million years for each stage, percentage
increase or decrease across stage boundary, which were are all based on
Phillips’ preferred timetree using Meredith’s DNA supermatrix which contained
169 species and 27 calibrations. The 2010 version of the geological time scale
was used to find the rates for dR27b and Mer82c, while the 2014 version
calculated the Emer15 rates. These authors decided to use different versions of
the geologic time scale. Emer15 recorded two speciation events that occurred
near the end of the Lutetian that were unrelated to Meredith’s taxon sampling,
which included deep splits in Soricidae and Emballonuridae which were not
included in the analyses

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In conclusion, Ghost lineages were
presumed to exist without having any fossil records, while zombie lineages were
found to have fossil records that are not compatible with the timetree dates.
Ghost lineages are expected to be products of incomplete fossil records, while
zombie lineages are only possible with inaccurate minimum ages of fossils or
when fossils have not been assigned to their proper taxonomic group .Even
though there is a great number of zombie lineages that contradict the fossil record,
Phillips’ timetree does contain various ghost lineages that are older than the
fossil record, having fewer incompatibilities compared to most other studies.
Fossils are unable to provide any conclusive evidence related to the ancestry
of extant mammals , due to Cretaceous and Paleocene fossils and modern
placental lineages being unrelated.

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