This is a link to Joanna Jurewicz's paper speculating on the presence of a doctrine of metempsychosis in the Rg Veda.
She gives an interesting treatment of the familiar 10.16.5-
5 Again, O Agni, to the Fathers send him who, offered in thee, goes with our oblations.
Wearing new life let him increase his offspring: let him rejoin a body, Jātavedas.
basing herself on the work of the Sri Lankan antropologist, Gananath Obeyesekere who stresses the ubiquity of the concept of reincarnation in 'small scale' societies and the manner in which it shores up ethnicity and diachronic identity.
However, in my view, the opposite point might, in the Hindu context, be more usefully be made- viz. reincarnation is systematically sublated, ethnicity is systematically sublated, diachronic identity is sublated, by something arising out of the potential for Universalization that exists in a transactional view of the world.
The Vedic funeral is of particular interest because it shows how- as in the modern Economic theory of externalities- no transaction is between two parties alone, all partake of it and all are thereby transfigured. What is conserved is symmetry properties of the system as a whole and it is this conservation alone that makes it meaningful to speak of karma and dharma.
In Judaism, similarly, the concept of ibbur- that is 'partial incarnation'- has the effect of conserving halachah (the law) even by halachah vein morin kein (the law which if known forbids the action it otherwise enjoins).
Does bodily resurrection at the eschaton, give flesh to a 'costly signalling' halachah whereas is it the case that ibbur is just a cheap talk variant?
Similarly, does the notion of samadhi imply that karma kanda is a 'costly signalling' Yoga while Raja Yoga is just cheap talk?
Yes, in my view, if cognitive linguistics is correct. No, if language, as something which has evolved, is in essence reverse mereological.