Department of Anthropology, University of Alabama, Tuscaloosa, Alabama, 35487, USA.
Department of Anthropology, University of North Carolina Wilmington, Wilmington, North Carolina, 28403, USA.
Am J Biol Anthropol. 2023 Sep;182(1):7-11. doi: 10.1002/ajpa.24741. Epub 2023 Apr 3.
Tattooing is not an evolved behavior, but it may be a phenotypic gambit to highlight immunological health. Phenotypic gambits are traits or behaviors that appear costly but occur at high rates as a honing process of natural selection not constrained by genetics. Tattooing is an ancient practice that is increasing in popularity worldwide, but it involves wounding the body, which seems counterintuitive because it challenges the immune system and makes one more susceptible to infection. But tattooing may represent a costly honest signal of fitness by "upping the ante" in an era of hygiene or a means to stimulate the immune system in a way that improves and highlights underlying fitness.
We investigated this hypothesis by assessing bacteria killing activity (BKA) in saliva samples collected during two studies of tattooing (N = 40). We compared previous tattoo experience (extent of body tattooed and hours spent being tattooed) to BKA before and after getting a new tattoo.
Tattoo experience positively predicts post-tattoo BKA (β = 0.48, p = 0.01), suggesting that people with more tattoo experience have a relatively more immediate and active immune response than those with less tattoo experience.
Tattoo experience may elevate innate immunological vigilance, which could aid in protecting against future dermal insults.
纹身并非一种进化行为，但它可能是一种突出免疫健康的表型策略。表型策略是指那些看似代价高昂但却以高频率出现的特征或行为，是自然选择的磨练过程，不受遗传的限制。纹身是一种古老的做法，在全球范围内越来越流行，但它涉及到对身体的伤害，这似乎与直觉相悖，因为它挑战了免疫系统，使人更容易感染。但是，纹身可能代表了一种代价高昂的诚实信号，表明在卫生时代或通过刺激免疫系统来提高和突出潜在健康水平的方式下，身体更健康。
我们通过评估在两次纹身研究（N=40）中收集的唾液样本中的细菌杀伤活性（BKA）来验证这一假设。我们比较了以前的纹身经验（纹身的身体部位和纹身时间）与新纹身前后的 BKA。
纹身经验与纹身后的 BKA 呈正相关（β=0.48，p=0.01），这表明纹身经验丰富的人比纹身经验较少的人有更直接和活跃的免疫反应。
纹身经验可能会提高先天免疫警觉性，这有助于防止未来的皮肤损伤。
