Data from: Crossing the (Wallace) line: local abundance and distribution of mammals across biogeographic barriers

Past and ongoing vertebrate introductions threaten to rearrange ecological
communities in the Indo-Malay Archipelago, one of Earth's most
biodiverse regions. But the consequences of these translocations are
difficult to predict. We compared local abundance and distributions in
four tropical mammal lineages that have crossed from Asia to Wallacea or
New Guinea. The local abundance of macaques (Macaca spp.), which naturally
crossed Wallace's Line, was higher in Sulawesi (east of the line;
mean = 3.7 individuals per camera station, 95% CI = 2.2: 5.1) than in
Borneo (west of the line; mean = 1.1, CI = 0.8: 1.4), but the local
abundance of Malay civets (Viverra tangalunga), Rusa deer, and Sus pigs
was similar in their native ranges and where they had been introduced by
humans east of Wallace's Line. Proximity to rivers increased Malay
Civet local abundance and decreased the local abundance of pigs in parts
of their introduced ranges (Maluku and New Guinea, respectively), while
having no effect on local abundance in their native ranges (Borneo) or
other areas where they have been introduced (Sulawesi). That local
abundance was higher east of Wallace's Line in just one of four
mammal lineages is consistent with findings from plant invasions, where
most species have similar abundance in their native and introduced ranges.
However, species’ ecology may change as they enter new communities, for
example, their patterns of abundance at local scales. This could make it
difficult to predict community structure in the face of ongoing species
introductions.