K-casein gene phylogeny of higher ruminants (Pecora, Artiodactyla).

To assess phylogenetic relationships among the higher ruminants (infraorder Pecora, order Artiodactyla), we analyzed K-casein DNA sequences, including 434 nucleotides of the fourth exon. The higher ruminant families Bovidae, Cervidae, Giraffidae, and Antilocapridae each have monophyletic K-casein sequences. Maximum parsimony and distance analyses identify Giraffidae as a sister group to either Cervidae or a Bovidae-Cervidae clade and Antilocapridae as a sister group to a Bovidae-Cervidae-Giraffidae clade. At a higher level these four families occur as a monophyletic clade relative to Tragulidae and Suidae. Within Cervidae, the subfamily Odocoileinae is monophyletic and Cervinae and Muntiacinae occur as independent lineages within a separate clade. Within Bovidae, the subfamilies Bovinae and Caprinae are monophyletic. Genera within Cervinae (Cervus, Elaphurus) and Bovinae (Bison, Bos) are paraphyletic. There is intraspecific allelic variation in Cervus elaphus, Odocoileus hemionus, and Bison bison. The rate of K-casein fourth exon DNA sequence evolution is estimated to be about 0.004 nucleotide substitutions per million years. The K-casein phylogeny is discussed relative to other molecular and morphological data.

Genetic variation in domestic reindeer and wild caribou in Alaska.

Reindeer (Rangifer tarandus tarandus) were introduced into Alaska 100 years ago and have been maintained as semidomestic livestock. They have had contact with wild caribou (R.t.granti) herds, including deliberate crossbreeding and mixing in the wild. Reindeer have considerable potential as a domestic animal for meat or velvet antler production, and wild caribou are important to subsistence and sport hunters. Our objective was to quantify the genetic relationships of reindeer and caribou in Alaska. We identified allelic variation among five herds of wild caribou and three herds of reindeer with DNA sequencing and restriction enzymes for three loci: a DQA locus of the major histocompatibility complex (Rata-DQA1), kappa-casein and the D-loop of mitochondrial DNA. These loci are of interest because of their potential influence on domestic animal performance and the fitness of wild populations. There is considerable genetic variation in reindeer and caribou for all three loci, including five, three and six alleles for DQA, kappa-casein and D-loop respectively. Most alleles occur in both reindeer and caribou, which may be the result of recent common ancestry or genetic introgression in either direction. However, allele frequencies differ considerably between reindeer and caribou, which suggests that gene flow has been limited.

Effect of effort on meal selection and meal acceptability in a student cafeteria.

Past laboratory and field studies show that the effort necessary to obtain food acts as a determinant of food selection and consumption. Two studies examined the impact of increasing the effort needed to obtain candy or potato chips on selection in a normal lunch setting. In the first study, food selection, acceptance and intake were obtained during the first week baseline and under the effort manipulation during the second week. With increased effort, candy selection dropped dramatically in week 2. Subjects substituted items from the desert, fruit and accessory food groups. In the second study, food selection and acceptance were measured during a 2-week baseline, a 3-week effort period, and a 3-week recovery period. With increased effort, potato chip selection dropped dramatically and only partially recovered in the last phase. Subjects substituted items from the starch food group. These results demonstrate that changes in the effort needed to obtain food can have a nutritional impact in an actual eating situation and could be an important part of a healthy eating strategy.

Effects of adding an Italian theme to a restaurant on the perceived ethnicity, acceptability, and selection of foods.

We investigated whether a change in the perceived ethnicity of a food can be produced without manipulating the food item itself, and if that change in ethnic perception is accompanied by a change in acceptability and food selection behavior. Italian and British foods were offered in a British restaurant for four days. Foods were offered for 2 days under control conditions, when the restaurant was decorated as usual. The identical foods then were offered in the restaurant for 2 more days under experimental conditions, when ethnic names were used on the menu to describe foods, and the restaurant was decorated with an Italian theme. Perceived ethnicity and acceptability of items were rated by customers each day, and item selection was tracked. The Italian theme increased selection of pasta and dessert items, and decreased the selection of fish. The Italian theme also increased the perceived Italian ethnicity of British pasta items, fish and veal, and increased the perceived Italian ethnicity of the meal overall. These findings show that changes in perceived ethnicity and food selection can be accomplished without altering food items, but merely by manipulating the environment, and may imply a unique strategy for increasing perceived menu variety.