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In this work, we have explored the expressiveness of combining simple mechanisms as a possible explanation for pigmentation pattern formation, where tissue growth plays a crucial role. Our motivation is not only to realistically reproduce natural patterns but also to get insights into the underlying biological processes. Therefore, we present a novel approach to generate realistic animal skin patterns. First, we describe the approximation of tissue growth by a series of discrete matrix expansion operations. Then, we combine it with an adaptation of Turing's non-linear reaction-diffusion model, which enforces upper and lower bounds to the concentrations of the involved chemical reagents. We also propose the addition of a single-reagent continuous autocatalytic reaction, called reinforcement, to provide a mechanism to maintain an already established pattern during growth. By careful adjustment of the parameters and the sequencing of operations, we closely match the appearance of a few real species. In particular, we reproduce in detail the distinctive features of the leopard skin, also providing a hypothesis for the simultaneous productions of the most common melanin types, eumelanin and pheomelanin.<\/jats:p>","DOI":"10.1145\/3386569.3392478","type":"journal-article","created":{"date-parts":[[2020,8,12]],"date-time":"2020-08-12T11:44:27Z","timestamp":1597232667000},"update-policy":"https:\/\/doi.org\/10.1145\/crossmark-policy","source":"Crossref","is-referenced-by-count":5,"title":["The leopard never changes its spots"],"prefix":"10.1145","volume":"39","author":[{"given":"Marcelo","family":"De Gomensoro Malheiros","sequence":"first","affiliation":[{"name":"FURG, Brazil"}]},{"given":"Henrique","family":"Fensterseifer","sequence":"additional","affiliation":[{"name":"UFRGS, Brazil"}]},{"given":"Marcelo","family":"Walter","sequence":"additional","affiliation":[{"name":"UFRGS, Brazil"}]}],"member":"320","published-online":{"date-parts":[[2020,8,12]]},"reference":[{"key":"e_1_2_2_1_1","doi-asserted-by":"publisher","DOI":"10.1016\/0022-5193(74)90128-3"},{"key":"e_1_2_2_2_1","doi-asserted-by":"publisher","DOI":"10.1016\/0022-5193(81)90109-0"},{"key":"e_1_2_2_3_1","doi-asserted-by":"publisher","DOI":"10.1103\/PhysRevE.78.031912"},{"key":"e_1_2_2_4_1","doi-asserted-by":"publisher","DOI":"10.1111\/cgf.12830"},{"key":"e_1_2_2_5_1","volume-title":"An ancient Turing-like patterning mechanism regulates skin denticle development in sharks. 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