The staging point, obviously

The quotes below refer to a couple of individuals buried in the Yampil Barrow Complex, in the forest-steppes of western Ukraine, who were featured recently in the Juras et al. paper on the maternal ancestry of the Corded Ware people (see here). In that paper they were labeled Late Eneolithic poz090 and Yamnaya poz224, respectively. Emphasis is mine:

The central burial of the oldest barrow, feature 1B was accompanied by a spill of yellow loess (on the east side) and the remains of wooden roofing located at the original ground level. The pit was rather irregular in shape, subrectangular, and was narrower than the neighbouring excavation of grave 1a. The adult male buried in it had been laid supine with the upper limbs slightly bent at the elbows and extended along the trunk and the lower limbs crouched with the knees turned upwards. Neither the skeleton nor the pit bottom were sprinkled with ochre (only trace amounts of a red colourant were found in the remains of a mat). This ritual is on the one hand close to the YC (Yamnaya Culture) rite and on the other to the Eneolithic burials of the ‘post-Stog’ type [Ivanova 2015: 282, 283].
…
Only in grave IV/8 was an intentional item of furnishing discovered: a regular blade knife insert made of good quality Dniester lint. Such tools are not a typical component of YC inventories [razumov 2011: 146, 147]. They are, however, a frequent element of grave goods offered to males in Corded Ware Culture (CWC) graves, a large number of which is known from Małopolska [Włodarczak 2006:30-32].
The radiocarbon measurements and funerary rite traits indicate that the graves from Prydnistryanske were dug in the older and middle phases of YC development, while the age of the youngest ones still stays in the first half of the 3rd millennium BC.

The source is a report from 2015 authored by many of the co-authors of Juras et al., titled Podolia as a cultural contact area in the 4th/3rd-2nd millennium BC (see here).
Until the Late Eneolithic this part of the North Pontic region was occupied by the Trypillia people, who were the quintessential “Old European” farmers (scroll down to the last abstract here). So judging by the burial characteristics and eastern mitochondrial haplotypes of poz090 and poz224, it’s clear that they weren’t indigenous to the region, but rather migrants, or the recent descendants of migrants, from the steppes. And, in all likelihood, people like them gave rise to the Corded Ware Culture of Northern Europe.
Obviously, I’m not arguing anything that wasn’t already argued well enough in the Juras et al. paper, but I thought I’d emphasize it with some juicy archaeological details that many of you might not be aware of.
See also…
Late PIE ground zero now obvious; location of PIE homeland still uncertain, but…

Source

https://xissufotoday.space/2018/08/the-staging-point-obviously/