Is the Kteily et al. 2015 "Ascent of Man" measure a measure of "blatant" dehumanization?

This post discusses a commonly used "blatant" measure of dehumanization. Let me begin by proposing two blatant measures of dehumanization:

1. Yes or No?: Do you think that members of Group X are fully human?

2. On a scale in which 0 is not at all human and 10 is fully human, where would you rate members of Group X?

I would interpret a "No" response for the first measure and a response of any number lower than 10 for the second measure as dehumanization of members of Group X. If there are no reasonable alternate interpretation for these responses, then these are face-valid unambiguous measures of blatant dehumanization.

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But neither above measure is the commonly used social science measure of blatant dehumanization. Instead, the the commonly used "measure of blatant dehumanization" (from Kteily et al. 2015), referred to as the Ascent measure, is below:

And here is how Kteily et al.'s 2015 described the ends of the tool (emphasis omitted):

Responses on the continuous slider were converted to a rating from 0 (least "evolved") to 100 (most "evolved")...

Note that participants are instructed to rate how "evolved" the participant considers the average member of a group to be and that these ratings are placed on a scale from "least evolved" to "most evolved", but these ratings are then interpreted as participant perceptions about the humanness of the group. This doesn't seem like a measure of blatant dehumanization if participants aren't asked to indicate their perceptions of how human the average member of a group is.

The Ascent measure is a blatant measure of dehumanization only if "human" and "evolved" are identical concepts, but these aren't identical concepts. It's possible to simultaneously believe that Bronze Age humans are fully human and that Bronze Age humans are less evolved than humans today. Moreover, I think that the fourth figure in the Ascent image is a Cro-Magnon that is classified by scientists as human, and Kteily et al. seem to agree:

...the image is used colloquially to highlight a salient distinction between early human ancestors and modern humans; that is, the full realization of cognitive ability and cultural expression

The perceived humanness of the fourth figure matters for understanding responses to the Ascent measure because much of the variation in responses occurs between the fourth figure and fifth figure (for example, see Table 1 of Kteily et al. 2015 and Note 1 below).

There is an important distinction between participants dehumanizing a group and participants rating one group lower than another group on a measure that participants interpret as indicating something other than "humanness", such as the degree of "realization of cognitive ability and cultural expression", especially because I don't think that humans need to have "the full realization of cognitive ability and cultural expression" in order to be fully human.

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NOTES

1. The Jardina and Piston TESS study conducted in 2015 and 2016 with only non-Hispanic White participants had a Ascent measure in which 66% and 77% of unweighted responses for the respective targets of Blacks and Whites were in the 91-to-100 range.

2. I made some of the above points in 2015 in the ANES Online Commons. Lee Jussim raised issues discussed above in 2018, and I didn't find anything earlier.

3. More Twitter discussion of the Ascent measure: here with no reply, here with no reply, here with a reply, here with a reply.