behaviors of passing through the phases of the test. When provided with a colored tag in a modified mark test, the fish attempted to scrape off this tag by scraping their bodies on the side of the mirror. Gordon Gallup believes the cleaner wrasses' behavior can be attributed to something other than recognizing itself in a mirror. Gallup has argued that a cleaner wrasse's job in life is to be aware of ectoparasites on the bodies of other fish, so it would be hyper aware of the fake parasite that it noticed in the mirror, perhaps seeing it as a parasite that it needed to clean off of a different fish. The authors of the study retort that because the fish checked itself in the mirror before and after the scraping, this means that the fish has self-awareness and recognizes that its reflection belongs to its own body. The cleaner wrasses, when tested, spent a large amount of time with the mirror when they were first getting acquainted with it, without any training. Importantly, the cleaner wrasses performed scraping behavior with the colored mark, and they did not perform the same scraping behavior without the colored mark in the presence of the mirror, nor when they were with the mirror and had a transparent mark. Following various objections, the researchers published a follow-up study in 2022, where they did the mirror test on a larger sample of wrasses and experimented with several marking techniques. The new results "increase[d] [the researchers'] confidence that cleaner fish indeed pass the mark test", although wrasses attempted to scrape off the mark only when it resembled a parasite. In 2016 a modified mirror test done on two captive Manta rays (Mobula birostris) showed that they exhibited behavior associated with self-awareness (i.e. contingency checking and unusual self-directed behavior). Animals that have failed Some animals that have reportedly failed the classic MSR test include: Mammals Carnivorans Sea lions (Zalophus californianus) Giant panda (Ailuropoda melanoleuca): In one study, 34 captive giant pandas of a wide range of ages were tested. None of the pandas responded to the mark and many reacted aggressively towards the mirror, causing the researchers to consider the pandas viewed their reflection as a conspecific. Dogs (Canis familiaris): Dogs either treat the image as another animal, or come to ignore it completely. Primates Stump-tailed macaque (Macaca arctoides) Crab-eating macaque (Macaca fascicularis) Rhesus macaque (Macaca mulatta):