Cats domesticated themselves

Hu, Y., Hu, S., Wang, W., Wu, X., Marshall, F. B., Chen, X., Hou, L. & Wang, C. (2013). Earliest evidence for commensal processes of cat domestication. Proceedings of the National Academy of Sciences, 201311439.

Domestic cats are one of the most popular pets globally, but the process of their domestication is not well understood. Near Eastern wildcats are thought to have been attracted to food sources in early agricultural settlements, following a commensal pathway to domestication. Early evidence for close human–cat relationships comes from a wildcat interred near a human on Cyprus ca. 9,500 y ago, but the earliest domestic cats are known only from Egyptian art dating to 4,000 y ago. Evidence is lacking from the key period of cat domestication 9,500–4,000 y ago. We report on the presence of cats directly dated between 5560–5280 cal B.P. in the early agricultural village of Quanhucun in Shaanxi, China. These cats were outside the wild range of Near Eastern wildcats and biometrically smaller, but within the size-range of domestic cats. The δ13C and δ15N values of human and animal bone collagen revealed substantial consumption of millet-based foods by humans, rodents, and cats. Ceramic storage containers designed to exclude rodents indicated a threat to stored grain in Yangshao villages. Taken together, isotopic and archaeological data demonstrate that cats were advantageous for ancient farmers. Isotopic data also show that one cat ate less meat and consumed more millet-based foods than expected, indicating that it scavenged among or was fed by people. This study offers fresh perspectives on cat domestication, providing the earliest known evidence for commensal relationships between people and cats.

More on stable isotopes to know feral cat diet on islands

Keitt, B. S., Wilcox, C., Tershy, B. R., Croll, D. A., & Donlan, C. J. (2002). The effect of feral cats on the population viability of black‐vented shearwaters (Puffinus opisthomelas) on Natividad Island, Mexico. Animal Conservation, 5(3), 217-223.

Insular breeding seabirds are likely to be particularly vulnerable to introduced mammalian predators because they often lack behavioural, morphological and life-history defenses against predation. We studied the life-history of the black-vented shearwater (Puffinus opisthomelas) on Natividad Island, Baja California Sur, Mexico, to examine its vulnerability to introduced feral cats. Using an allometric equation, we estimated that feral cats consumed 328 g of food day-1 to satisfy their nutritional requirements. We used stable isotope analysis of cat scat to estimate that 90% of the cats' diet was composed of shearwaters. Using data from our focal species and from the closely related manx shearwater (Puffinus puffinus), we created a demographic model to evaluate the effects of cat population size on the annual growth rate (λ) of the shearwater. The annual growth rate for black-vented shearwaters was estimated to be 1.006 in the absence of cat predation. With predation, we estimated that annual growth rate declined approximately 5% for every 20 cats in a population of 150,000 birds. Persistence times of bird colonies decreased both with an increase in the size of the feral cat population and with a decrease in the size of the initial bird population.

Stable isotopes to know cat's diet on islands

MECKSTROTH, A. M., MILES, A. K. & CHANDRA, S. 2007. Diets of Introduced Predators Using Stable Isotopes and Stomach Contents. The Journal of Wildlife Management, 71: 2387–2392.

In a study of predation on ground-nesting birds at South San Francisco Bay (South Bay), California, USA, we analyzed stomach contents and stable isotopes of carbon and nitrogen to identify commonly consumed prey. We obtained the stomach contents from 206 nonnative red foxes (Vulpes vulpes regalis) collected in the South Bay area and Monterey County during 1995–2001 and from 68 feral cats (Felis silvestris) from the South Bay area during 2001–2002. We determined prey identity, biomass, and frequency, described seasonal diet trends, and derived an Index of Relative Importance. Avian species were the most frequent prey we found in the stomachs of red foxes from South Bay (61%), whereas small rodents were most frequent for red foxes from Monterey County (62%). Small rodents were the most frequent prey we found in feral cats (63%). Carbon and nitrogen isotopic signatures for foxes supported stomach content findings. However, isotope results indicated that cats received a majority of their energy from a source other than rodents and outside the natural system, which differed from the stomach content analysis. We demonstrated the utility of both stable isotope and stomach content analyses to establish a more complete understanding of predators' diets. This information aids natural resource managers in planning and evaluating future predator-removal programs and increases our understanding of the impacts of nonnative foxes and cats on native species.



Petra Quillfeldt, P.,  I. Schenk, R.A. R. McGill, I. J. Strange, J.F. Masello, A. Gladbach, V. Roesch & R.W. Furness. 2008.Introduced mammals coexist with seabirds at New Island, Falkland Islands: abundance, habitat preferences, and stable isotope analysis of diet. Polar Biology 31:333–349 

The largest known colony of Thin-billed prions Pachyptila belcheri has been coexisting with introduced mammals for more than 100 years. Three of the introduced mammals are potential predators of adults, eggs and chicks, namely ship rats Rattus rattus, house mice Mus musculus and feral cats Felis catus. We here determine habitat preferences over three seasons and dietary patterns of the unique set of introduced predators at New Island, Falkland Islands, with emphasis on the ship rats. Our study highlights spatial
and temporal diVerences in the levels of interaction between predators and native seabirds. Rats and mice had a preference for areas providing cover in the form of the native tussac grass  Parodiochloa  xabellata or introduced gorse  Ulex europaeus. Their diet differed markedly between areas, over the season and between age groups in rats. During the incubation period of the prions in November–December, ship rats had mixed diets, composed mainly of plants and mammals, while only 3% of rats had ingested birds. The proportion of ingested birds, including scavenged, increased in the prion chick-rearing period, when 60% of the rats consumed prions. We used 13C and 15N to compare the importance of marine-derived food between mammal species and individuals, and found that rats in all but one area took diet of partly marine origin, prions being the most frequently encountered marine food. Most house mice at New Island mainly had terrestrial diet. The stable isotope analysis of tissues with different turnover times indicated that individual rats and mice were consistent in their diet over weeks, but opportunistic in the short term. Some individuals (12% of rats and 7% of mice) were highly specialized in marine-derived food. According to the isotope  ratios in a small sample of cat faeces, rodents and rabbits were the chief prey of cats at New Island. Although some individuals of all three predators supplement their terrestrial diet with marine-derived food, the current impact of predation by mammals on the large population of Thinbilled prions at New Island appears small due to a number of factors, including the small size of rodent populations and restriction mainly to small areas providing cover.