The case of Marius, a young giraffe suppressed in the name of species conservation in February 2014 at Copenhagen Zoo as a surplus, created both considerable media outcry and heated debate both in science and ethics. Debate that even today, after almost 5 years still has not subsided. In this contribution, we try to confront with the reiterated question ‘are zoos unethical?’, discussing ‘from the inside’ the presuppositions of specie conservation in zoos today. Following the main questions that have been raised on the web regarding the case of Marius, we suggest that in ethical relevant issues as Marius’ case, a standardized and contextualized ethical analysis on a case-by-case basis can be of help. By clarifying assumptions, considering the values at stake, the scientific aspects and the needs of the stakeholders involved, it is possible to improve the ethical decision-making process. This process can favor the transparency and consistency of the work of the zoos. The request for standardized ethical assessments through ethics committees and the use of tools for analysys has already emerged in different zoological context. If they want to continue to have support from society, it is mandatory for modern zoos to make a commitment to take directly into consideration the difficulties and uncertainties that distinguish the new social ethics for animals.
