In to Meredith’s taxon sampling, which included deep splits

In this article, Phillips has an
argument that a mammal’s large body size and the length of their lifespans are
linked to transference errors, causing a rise in previous estimates of
interordinal divergence times. Later on, 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
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, believingl 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 wayward 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.