The initial peopling of the Americas is a contested and evolving topic 1 , with the exact timing of the first arrivals still unknown. Historically, Mexico's understudied and controversial archaeological record has remained on the periphery of First Americans research 2 . However, in recent years, investigations have shown reliable evidence of a late-Pleistocene and early-Holocene human presence in the northwest region 3,4 , the Chiapas Highlands 5 , Central Mexico 6 , and the Caribbean coast [7][8][9] . Evidence of human presence at Chiquihuite Cave extends this antiquity and attests to the cultural variability of older-than-Clovis sites [10][11][12][13][14][15][16][17] and the earliest humans on the continent. Site settings and excavation context.

Continental strata and volcanic rocks of the type Huizachal Group in Valle deHuizachal record arc magmatism and subsequent crustal extension prior to seafl oor spreading in the Gulf of Mexico. The older La Boca Formation consists of two informal members, a lower unit of siliciclastic and volcanic rocks discordantly overlain by a predominantly siliciclastic upper member. The younger La Joya Formation is an upwardfi ning, alluvial-braided fl uvial succession with a basal conglomerate. U-Pb detrital-zircon ages (n = 576) from six Huizachal Group sandstones (fi ve from La Boca and one from La Joya) consist of four groups indicating a mixed provenance: (1) Grenville grains (~1.3-1.0 Ga) derived from Gondwana (Novillo Gneiss); (2) earlymiddle Paleozoic grains (430-300 Ma) derived from peri-Gondwanan accreted rocks (Granjeno Schist); (3) Permo-Triassic grains (296-222 Ma) derived from volcanic and plutonic rocks (West Pangaean arc) and/or turbidites (Guacamaya Formation); and (4) Early-Middle Jurassic grains (199-164 Ma), locally derived from the Nazas arc. Groups 1-3 increase in abundance upsection as a result of unroofi ng of Jurassic volcanic and sedimentary carapace from uplifted basement. estratigráfi ca por debajo de depósitos inferidos del Oxfordiano.

Knowledge gaps exist in the socio-ecological systems of small touristic islands in Latin America. Understanding tourists’ perceptions of their environmental knowledge can help plan actions to prevent natural capital loss necessary for local economies. Tourists’ perceptions of a touristic hotspot, Holbox Island, were documented. Surveys demonstrated that tourists are aware of their environmental impacts and are interested in minimizing these. Results were compared with results on Bocas del Toro, Panama. Tourists’ perceptions had similarities among sites driven by similarities in tourists’ populations with a common geographic origin. Tourists lack site-specific knowledge to steer them towards environmentally conscious decisions in both regions. Findings suggest the need to promote local actions to gain tourists’ understanding about their destination and support education programs on island conservation. Addressing these needs can help build resilience to overcome the adverse socio-environmental effects of tourism, environmental disasters, and health crises as COVID-19 on small islands.

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