![]() However, ruminants are largely considered poor seed dispersers for many plant species because of their complex digestive process (Barlow, 2000 Cosyns, Delporte, & Hoffman, 2005 Prasad, Krishnaswamy, Chellam, & Goyal, 2006 but see Janzen, 1982).Įxperimental studies indicate that the seeds of some proposed anachronistic fruits sprout and produce higher quality seedlings after passing through the guts of Pleistocene ecological analogs (e.g., Asian Elephant, Elephas maximus L., Boone et al., 2015), while others have shown that native extant mammals could also be effective seed dispersers for these plants (Cypher & Cypher, 1999 Roehm & Moran, 2013). Ruminant mammals also suffered high Pleistocene extinction rates, but still exist in moderate diversity throughout temperate parts of the continent. Today, there are no surviving large, nonruminant mammals in temperate North America, with the exception of the collard peccary ( Pecari tajacu L.) in the southwest United States. It has been suggested that nonruminant herbivores, such as mastodons, mammoths, gomphotheres, horses, and giant ground sloths, because of their high mobility and relatively mild guts, would have made particularly effective seed dispersers (Boone et al., 2015 Janzen & Martin, 1982). The scope of possible large mammal seed dispersers during the Pleistocene is extensive. Some species (squash, Curcubita spp.) may even have been on a pathway to extinction in the post‐Pleistocene world because of their reduction in seed dispersal, but survived through domestication by aboriginal humans (Kistler et al., 2015). For example, the Osage orange ( Maclura pomifera Raf.) was historically found (at the time of European settlement) in small areas of Texas, Oklahoma, and Arkansas, but today it has spread by human dispersal throughout most of temperate North America (Barlow, 2000). This loss of potential seed dispersers may have affected the distance seeds travel from parent plants and may explain why the realized range (without human assistance) was often smaller than the potential range of these species (Berry, 1916 Burton, 1990 Murphy, 2001 Skallerup, 1953). For instance, several trees have fruits that offer a high potential energy reward, yet appear to have no living dispersers (Barlow, 2001). It has been hypothesized that the end‐Pleistocene extinction event in North America-particularly the disappearance of numerous large mammals-resulted in the loss of co‐evolved plant–animal relationships. Several North American plants are hypothesized to be anachronistic (Barlow, 2001), in that they lack living seed dispersers (Janzen, 1982 Janzen & Martin, 1982). ![]() We argue that changes in the relative abundance of mammals during the Anthropocene may be modifying seed dispersal patterns, leading to potential changes in forest community composition. However, human‐induced changes in mammal communities could be affecting successful seed dispersal. Our results suggest the American persimmon evolved to attract a variety of seed dispersers and thus is not anachronistic. Conversely, potential living seed dispersers were rarely detected. Seven vertebrate species fed upon persimmon fruits, with the white‐tailed deer ( Odocoileus virginianus)-a species not capable of dispersing persimmon seeds-comprising over 90% of detections. Under field conditions, persimmon fruits were palatable on the parent tree and on the ground for an equal duration, but most fruits were consumed on the ground. Gut passage did not affect sprouting success, but did tend to decrease time to sprout and increase seedling quality. Persimmon seeds excreted by raccoons, coyotes, and elephants survived gut transit. We tested gut passage effects on persimmon seeds using three native living species, the raccoon ( Procyon lotor), Virginia opossum ( Didelphis virginiana), and coyote ( Canis latrans), and two Pleistocene analogs the Asian elephant ( Elephas maximus) and alpaca ( Vicugna pacos). We tested this hypothesis for the American persimmon ( Diospyros virginiana) by studying the effects of gut passage of proposed seed dispersers on seedling survival and growth, natural fruiting characteristics, and modern animal consumption patterns. ![]() Several North American trees are hypothesized to have lost their co‐evolved seed disperser during the late‐Pleistocene extinction and are therefore considered anachronistic. ![]()
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