Ancient proteins resolve the evolutionary history of Darwin's South American ungulates.

No large group of recently extinct placental mammals remains as evolutionarily cryptic as the approximately 280 genera grouped as 'South American native ungulates'. To Charles Darwin, who first collected their remains, they included perhaps the 'strangest animal[s] ever discovered'. Today, much like 180 years ago, it is no clearer whether they had one origin or several, arose before or after the Cretaceous/Palaeogene transition 66.2 million years ago, or are more likely to belong with the elephants and sirenians of superorder Afrotheria than with the euungulates (cattle, horses, and allies) of superorder Laurasiatheria. Morphology-based analyses have proved unconvincing because convergences are pervasive among unrelated ungulate-like placentals. Approaches using ancient DNA have also been unsuccessful, probably because of rapid DNA degradation in semitropical and temperate deposits. Here we apply proteomic analysis to screen bone samples of the Late Quaternary South American native ungulate taxa Toxodon (Notoungulata) and Macrauchenia (Litopterna) for phylogenetically informative protein sequences. For each ungulate, we obtain approximately 90% direct sequence coverage of type I collagen α1- and α2-chains, representing approximately 900 of 1,140 amino-acid residues for each subunit. A phylogeny is estimated from an alignment of these fossil sequences with collagen (I) gene transcripts from available mammalian genomes or mass spectrometrically derived sequence data obtained for this study. The resulting consensus tree agrees well with recent higher-level mammalian phylogenies. Toxodon and Macrauchenia form a monophyletic group whose sister taxon is not Afrotheria or any of its constituent clades as recently claimed, but instead crown Perissodactyla (horses, tapirs, and rhinoceroses). These results are consistent with the origin of at least some South American native ungulates from 'condylarths', a paraphyletic assembly of archaic placentals. With ongoing improvements in instrumentation and analytical procedures, proteomics may produce a revolution in systematics such as that achieved by genomics, but with the possibility of reaching much further back in time.

Archibald Menzies on Albemarle Island, Galápagos archipelago, 7 February 1795.

Menzies made the earliest extant botanical collections in the Galápagos; five sheets, representing three endemic species, are known. Menzies's own account of the visit is also extant and is transcribed here from his manuscript journal.

Genotypic diversity of mutans streptococci in Brazilian nursery children suggests horizontal transmission.

Streptococcus mutans strains were isolated from cohorts of Brazilian nursery school children and genotyped by arbitrarily primed PCR and restriction fragment length polymorphism analysis. Of 24 children with two to five S. mutans isolates, 29% carried two or more genotypes. The presence of matching genotypes of S. mutans among children attending one nursery suggests horizontal transmission.

A programme for computer aided identification of phlebotomine sandflies of the Americas (CIPA)--presentation and check-list of American species.

The CIPA programme is a collaborative project including two entomologists from France and seven from South and Central America countries. Its objective is the development of an expert system for computer aided identification of phlebotomine sandflies from the Americas. It also includes the formation of data bases for bibliographic, taxonomic and biogeographic data. Participant consensus on taxonomic prerequisites, standardization in bibliographic data collections and selection of descriptive variables for the final programme has been established through continuous communication among participants and annual meetings. The adopted check-list of American sandflies presented here includes 386 specific taxa, ordered into three genera and 28 sub-genera or species groups.

Survival of children and adolescents with acute lymphoid leukemia. A study of American Indians and Hispanic and non-Hispanic whites treated in New Mexico (1969 to 1986).

During the period 1969 to 1986, 196 American Indian and Hispanic and non-Hispanic white children and adolescents (ages, 0 to 19 years) were treated for acute lymphoid leukemia (ALL) at the University of New Mexico affiliated institutions. There were 28 American Indians (14%), 91 Hispanic whites (46%), and 77 non-Hispanic whites (39%). Median survivals for patients undergoing antileukemic therapy ranged from 8 months for American Indian boys to 140 months for non-Hispanic white girls. American Indian boys had the highest initial median leukocyte count (WBC) at 23.8 X 10(9)/l. Compliance problems occurred most commonly among American Indian children of both genders. Other clinical and pathologic features evaluated in this study were distributed similarly among the ethnic gender groups. Multi-variate analysis revealed that independent prognostic variables for survival included initial WBC, age, and gender. Ethnicity and compliance problems were possible, but confounded, prognostic variables. To the authors' knowledge this represents the most comprehensive study to date of ALL in American Indian patients.

Childhood cancer epidemiology in New Mexico's American Indians, Hispanic whites, and non-Hispanic whites, 1970-82.

The statewide population-based New Mexico Tumor Registry identified 473 malignant tumors among children of ages 0-14 years, during the period 1970-82. There were 235 non-Hispanic whites (50%), 189 Hispanic whites (40%), 38 American Indians (8%), and 11 other nonwhites (2%). The average annual age-adjusted incidence rates per million for non-Hispanic whites were 138.6 for males and 108.3 for females; for Hispanic whites, the rates were 108.5 for males and 80.9 for females; for American Indians, the rates were 75.5 for males and 78.0 for females. The incidence rates for all sites of cancer combined were lower for Hispanics and American Indians than for New Mexico's non-Hispanic whites and U.S. whites. Leukemia was the most common cancer in all racial-ethnic groups. In comparison with U.S. whites, American Indians were at low risk for leukemias, lymphomas, central nervous system (CNS), sympathetic nervous system (SNS), and kidney tumors and were at high risk for retinoblastoma, bone, and sex organ tumors. Hispanics were at low risk for CNS, SNS, kidney, sex organ, and liver tumors. Hispanic and non-Hispanic white males both were at increased risk for melanoma.