Do acquired characteristics show common ancestors?

yes they do

Explanation:

Acquired characteristics, by definition, are characteristics that are gained by an organism after birth as a result of external influences or the organism's own activities which change its structure or function and cannot be inherited.

Explanation:

The more similar the two species are, the more their niche overlaps and the more competition there is.

The most interesting results obtained in animal models of passive immunotherapies developed according to the “amyloid-beta cascade hypothesis” and the “Tau hypothesis” are monoclonal antibodies that directly or indirectly target Aβ plaques or neurofibrillary tangles. Unfortunately, these therapeutic antibodies cannot replicate their promising effects on humans at the clinical phase. Despite this, we still hope to learn from these failures and to explore new pathways. The great effects obtained in animals with passive immunotherapy suggest that this technology may be an important key to curative treatment. The remaining challenge is to find a way to achieve the same encouraging results for humans. Alzheimacy expects to join hands with global partners to focus on the development of therapeutic antibodies for Alzheimer’s disease (AD) and continue to fight against this disease.

https://www.creativebiomart.net/alzheimacy/therapeutics/therapeutic-antibody/