04307nas a2200337 4500008004100000245015700041210006900198300001000267490000700277520322600284653002603510653001703536653001803553653001403571653001503585653001303600100002703613700001903640700002403659700002003683700002703703700002103730700002103751700003003772700002203802700002703824700001903851700002903870700002703899856004303926 2019 eng d00aMigratory birds as vehicles for parasite dispersal? Infection by avian haemosporidians over the year and throughout the range of a long-distance migrant0 aMigratory birds as vehicles for parasite dispersal Infection by  a83-960 v463 a

Aim

The role of migratory birds in the spread of parasites is poorly known, in part because migratory strategies and behaviours potentially affecting transmission are not easy to study. We investigated the dynamics of infection by blood parasites through the annual cycle of a long‐distance Nearctic–Neotropical migratory songbird to examine the role of this species in dispersing parasites between continents.

Location

The Americas.

Taxon

Grey‐cheeked Thrush (Catharus minimus, Aves, Passeriformes, Turdidae), Birds.

Methods

We used molecular and microscopy screening of haemosporidian parasites (Plasmodium, Haemoproteus, and Leucocytozoon) to examine the prevalence, distribution, and diversity of lineages through the annual cycle (breeding, migration, and wintering) of the grey‐cheeked thrush in North and Central America, Santa Marta mountains, the Andes, and the Amazon. We aimed to identify transmission areas, to examine the degree of sharing of haemosporidian lineages with resident birds in various areas and to assess the potential role of immunologically naïve juvenile individuals in parasite transmission.

Results

Prevalence and lineage diversity of haemosporidians varied significantly over time, being higher during breeding and fall and spring migration, and declining during wintering. Grey‐cheeked thrush shared few parasite lineages with tropical resident birds and slightly more lineages with other migratory and resident boreal species. We detected gametocytes in blood during spring migration stopover, but these were of lineages not found in resident tropical birds, indicating relapses of parasites transmitted elsewhere. Transmission likely occurs mostly on the breeding grounds, where juveniles and adults carried lineages restricted to closely related species of thrushes and other species of boreal birds.

Main conclusions

Long‐distance migratory songbirds are likely not important dispersers of blood parasites because there are ecological and evolutionary barriers to the interchange of parasites across vastly separated areas. Further work with thorough spatial and temporal sampling across other species, and considering the role of vectors, is necessary to understand the ecological and evolutionary factors explaining the distribution of parasites over broad scales.

10aGrey‐cheeked thrush10aHaemoproteus10aLeucocytozoon10aMigration10aPlasmodium10astopover1 aPulgarín-R, Paulo, C.1 aGómez, Camila1 aBayly, Nicholas, J.1 aBensch, Staffan1 aFitzGerald, Alyssa, M.1 aStarkloff, Naima1 aKirchman, J., J.1 aGonzález-Prieto, Ana, M.1 aHobson, Keith, A.1 aUngvari-Martin, Judith1 aSkeen, Heather1 aCastaño, María, Isabel1 aCadena, Carlos, Daniel uhttp://doi.wiley.com/10.1111/jbi.1345302362nas a2200277 4500008004100000245016000041210006900201300001200270490000800282520152300290653000901813653001601822653000901838653001101847653001401858653000901872653001501881653002601896653002401922653002001946653001301966100002001979700001901999700001502018856005102033 2009 eng d00aStable Isotopes Reveal Seasonal Competition for Resources Between Late Pleistocene Bison (Bison) and Horse (Equus) from Rancho La Brea, Southern California0 aStable Isotopes Reveal Seasonal Competition for Resources Betwee a153-1600 v2713 a

Determining how organisms partition or compete for resources within ecosystems can reveal how communities are assembled. The Late Pleistocene deposits at Rancho La Brea are exceptionally diverse in large mammalian carnivores and herbivores, and afford a unique opportunity to study resource use and partitioning among these megafauna. Resource use was examined in bison and horses by serially sampling the stable carbon and oxygen isotope values found within tooth enamel of individual teeth of seven bison and five horses. Oxygen isotope results for both species reveal a pattern of seasonal enamel growth, while carbon isotope values reveal a more subtle seasonal pattern of dietary preferences. Both species ate a diet dominated by C3 plants, but bison regularly incorporated C4 plants into their diets, while horses ate C4 plants only occasionally. Bison had greater total variation in carbon isotope values than did horses implying migration away from Rancho La Brea. Bison appear to incorporate more C4 plants into their diets during winter, which corresponds to previous studies suggesting that Rancho La Brea, primarily surrounded by C3 plants, was used by bison only during late spring. The examination of intra-tooth isotopic variation which reveals intra-seasonal resource use among bison and horse at Rancho La Brea highlights the utility of isotopic techniques for understanding the intricacies of ecology within and between ancient mammals.

10aC-1310aCompetition10aDiet10aEnamel10aMigration10aO-1810aPopulation10aResource partitioning10aSpecies coexistence10aStable isotopes10aUngulata1 aFeranec, R., S.1 aHadley, E., A.1 aPaytan, A. uhttp://dx.doi.org/10.1016/j.palaeo.2008.10.00501892nas a2200169 4500008004100000245007000041210006700111300001200178490000600190520140100196653001301597653002201610653001801632653001401650100001701664856004101681 2001 eng d00aMaize, Matrilocality, Migration, and Northern Iroquoian Evolution0 aMaize Matrilocality Migration and Northern Iroquoian Evolution a151-1820 v83 a

The co-occurrence of matrilocality and maize-based agriculture among historical northern Iroquoian groups of New York and southern Ontario has long been of interest to anthropologists and archaeologists. The traditional explanation of this association is that gradual evolution of maize-based agriculture through female labor enhanced female status in families, which resulted in matrilocality. Dean Snow (1995a) recently challenged this in situ hypothesis of matrilocality by arguing that the sudden appearance of maize-based agriculture and matrilocality can only be explained by the migration of ancestral Iroquoian agriculturists into areas already inhabited by other people. Matrilocality arose because it allowed a focus on external warfare by men against the hostile original inhabitants. In contrast, and based on a general model of maize agriculture evolution and the effects of postmarital residence patterns on that model, I argue that neither in situ development hypothesis nor Snow's migration hypothesis affect the coevolution of matrilocality and maize agriculture, and that their “sudden” appearance cannot be used as evidence in support of either hypothesis. I also show that current archaeological evidence for maize agriculture and matrilocality support a gradual coevolution of maize agriculture and matrilocality rather than the sudden appearance argued by Snow.

10aIroquois10amaize agriculture10amatrilocality10aMigration1 aHart, J., P. uhttp://www.jstor.org/stable/20177438