Recent analyses of global Holocene datasets (Coles and Sparks 2006; Deligne et al. 2010; Furlan 2010) demonstrate a rapid decrease in historical recording back to 1500 AD, with possible change points at 1500 and 1900 (Furlan 2010).
Because of this more rapid decrease in historical data compared with geological data, Brown et al. (2014) excluded eruptions less than 1,000 years BP from their analysis to understand geological data.
In the historical group, a slight decrease in hypoxemia (SpO2 ≤91%) and hyperoxemia (SpO2 ≥97%) periods was found after 7 days after admission compared with the other two periods.
We can conclude that a decrease in the historical strength of natural selection relative to drift appears unlikely to explain higher TE abundance across the genus Drosophila.
The notable E-M81 frequency decrease in the historical sample, relative to the indigenous one, is in agreement with a strong European replacement of the indigenous males at the beginning of the conquest [ 5].
However, retrospective analyses of ribavirin-treated CHHF virus infected cohorts (compared with untreated historical controls) often report a decrease in CCHF-associated death if given within 72 h after the onset of symptoms (3 ).
Similarly to E-M81, the frequencies of E-M78 and J-M267 decrease in the historical and present-day Canary populations, again highlighting the strong demic impact of the European colonists before the 17th 18th centuries.
Although testing for the precise mechanism of the proposed historical increases and decreases in BRC repeat number is beyond the scope of this paper, we argue that the findings from population genetic and phylogenetic analyses of Drosophila species [18], address an interesting phenomenon surrounding an important feature of a gene pertinent to human health.
This actually corroborates that semen quality might have decreased temporarily as suggested by the meta-analysis by Carlsen et al. 1 Whereas the historical data point to a temporal decrease in sperm concentration and total sperm counts, there is no such data to support a similar trend in the percentages of normal spermatozoa in each ejaculate.
However, in the absence of a historical baseline, we cannot confirm either a decrease in genetic membership to source populations, or an increase in local genetic membership, as comparing historical and contemporary samples would have been necessary to test these hypotheses.
