If an archaeological perspective is key to conservation efforts, it also challenges elements of their foundation. If change is the only constant in human–ecology relationships, it remains unclear what “natural” targets ecological restoration should aim for (139). The wholesale appropriation of land and resources for environmental ends—“green grabbing”—at the expense of the needs and livelihoods of local and indigenous groups (often seen as destructive of pristine ecologies) is also further problematized (146). Appreciation of historical data shifts conservation ecology away from concern with a return to original ecological conditions, suggesting the need for pragmatic solutions that acknowledge the integral role humans have long played in shaping natural systems (36, 139). The impact of human agency on ecosystems is neither completely avoidable nor entirely undesirable. People have inhabited a growing range of environments at ever increasing densities only through the continual anthropogenic transformation of ecosystems. Rather than an impossible return to pristine conditions, what is needed is the historically informed management of emerging novel ecosystems to ensure the maintenance of ecological goods and services (139). Such efforts need to account for the needs of all stakeholders and balance local livelihoods against first world agendas.

Third, there is widespread evidence for increasing rates of human-mediated species translocation, extinction, and ecosystem and biodiversity reshaping through time. This acceleration is not constant but is characterized by pulses and pauses that reflect cultural, ecological, and climatic transformations at local, regional, and global scales. These changes have increasingly concentrated biomass into particular sets of human-favored plants and animals (134).

One of the major outcomes of the Neolithic was the inexorable spread of agriculture from ∼14–20 centers of early domestication (56) to encompass large swaths of the Old and New Worlds. This expansion had unprecedented and enduring impacts on species distributions. Key among these transformations was the promotion and expansion of a range of human-favored taxa, including newly created species (and subspecies) of domesticated crops and animals. Cumulative archaeological data show that crops and animals saw significant prehistoric and historic range expansion (Fig. 3). The scale of agriculture and land use in some regions was significant; for example, expansion of land area used for livestock and rice (Oryza sativa) paddy agriculture was sufficient to increase atmospheric methane emissions between 4,000 and 1,000 y B.P. (57) whereas deforestation and tillage are suggested to have contributed to increasing CO2 over the past 8,000 y (58).

Species translocations to islands were so common in the past that archaeologists often speak of “transported landscapes” (84). These new landscapes included a broad range of domesticated animals, commensals, crops, weeds, microbes, and other species carried by humans. For example, Neolithic colonizers who arrived on Cyprus brought domestic cereals, pulses, sheep, goat, cattle, pigs, domestic dogs, and cats (Felis catus), as well as mainland game animals such as fallow deer (Dama dama), fox (Vulpes vulpes), and wild boar beginning 10.6 ka (64, 85). Polynesian people, expanding across the Pacific after ∼3,500 y B.P. (84), introduced a broad range of domesticated species, including the crops taro (Colocasia esculenta), yam (Dioscorea spp.), and banana (Musa spp.), and such animals as the domestic pig, chicken, dog, and Pacific rat (Rattus exulans). In the Caribbean, Archaic and Ceramic period peoples introduced a variety of species, including wild avocado (Persea americana), manioc/cassava (Manihot esculenta), maize (Zea mays), tobacco (Nicotiana rustica), and various trees, as well as dogs, opossums (Didelphis sp.), guinea pigs (Cavia porcellus), and shrews (Nesophontes edithae) (86).

The human-mediated translocation of species now dates back to the Late Pleistocene. For example, the northern common cuscus (Phalanger orientalis), endemic to New Guinea, was transported to eastern Indonesia, the Solomon Islands, and the Bismarck Archipelago beginning ∼20–23 ka, becoming a key subsistence species (26, 27). Other taxa were also moved; together with a species of bandicoot (Echymipera kalubu) and the Admiralty cuscus (Spilocuscus kraemeri), the Canarium indicum tree was introduced to Manus by ∼13 ka, followed a few millennia later by the rat Rattus praetor (26). Translocation patterns mirror patterns of maritime obsidian exchange in Melanesia in the Late Pleistocene and Early Holocene (26).