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. Later on, he makes a suggestion 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 a soft explosive
model would allow the Xenarthra, Afrotheria, Euarchontoglires, and
Laurasiatheria lineages to emerge during the Cretaceous period. 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 (dR27b) 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 not being able to find any relationships
between Cretaceous and Paleocene fossils and modern placental lineages.