PubMed · 7477338
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B Wood. 1995-11-16. Australopithecus goes west.. https://doi.org/10.1038/378239b0
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The site of Longgupo Cave was discovered in 1984 and excavated in 1985-1988 by the Institute of Vertebrate Paleontology and Paleoanthropology (Beijing) and the Chongqing National Museum (Sichuan Province). Important finds include very archaic hominid dental fragments, Gigantopithecus teeth and primitive stone tools. Palaeomagnetic analysis and the presence of Ailuropoda microta (pygmy giant panda) suggested that the hominid-bearing levels dated to the earliest Pleistocene. In 1992, joint Chinese-American-Canadian geochronological research corroborated the age using electron spin resonance (ESR) analysis. We report here that the hominid dentition and stone tools from Longgupo Cave are comparable in age and morphology with early representives of the genus Homo (H. habilis and H. ergaster) and the Oldowan technology in East Africa. The Longgupo dentition is demonstrably more primitive than that seen in Asian Homo erectus. Longgupo's diverse and well preserved Plio-Pleistocene fauna of 116 species provide a sensitive contextual base for interpreting the early arrival of the genus Homo in Asia.
Chloroplast DNA restriction-site variation was surveyed among 40 accessions representing all 11 species of giant senecios (Dendrosenecio, Asteraceae) at all but one known location, plus three outgroup species. Remarkably little variation (only 9 variable sites out of roughly 1000 sites examined) was found among the 40 giant senecio accessions, yet as a group they differ significantly (at 18 sites) from Cineraria deltoidea, the closest known relative. This pattern indicates that the giant senecios underwent a recent dramatic radiation in eastern Africa and evolved from a relatively isolated lineage within the Senecioneae. Biogeographic interpretation of the molecular phylogeny suggests that the giant senecios originated high on Mt. Kilimanjaro, with subsequent dispersion to the Aberdares, Mt. Kenya, and the Cherangani Hills, followed by dispersion westward to the Ruwenzori Mountains, and then south to the Virunga Mountains, Mt. Kahuzi, and Mt. Muhi, but with dispersion back to Mt. Elgon. Geographic radiation was an important antecedent to the diversification in eastern Africa, which primarily involved repeated altitudinal radiation, both up and down the mountains, leading to morphological parallelism in both directions. In general, the plants on a given mountain are more closely related to each other than they are to plants on other mountains, and plants on nearby mountains are more closely related to each other than they are to plants on more distant mountains. The individual steps of the geographic radiation have occurred at various altitudes, some clearly the result of intermountain dispersal. The molecular evidence suggests that two species are extant ancestors to other species on the same or nearby mountains.
For 20 years, the prospect of anti-malarial vaccination has aroused many hopes, but in the end, it has mostly given rise to doubts and disappointment. If most attempts have been to no avail, this is because the issue at stake is amazingly difficult. Besides the very complex antigenic structure of the protozoa Plasmodium, there is first the existence of at least three different targets during the plasmodial cycle, then the necessity of appropriate adjuvants and, most of all, the imperfection of our experimental models. Recently, Pattaroyo and the various groups who worked with him have eventually met success with vaccine trials in man: they used a synthetic antigene, SPf66, on volunteers in South America, then on a larger population sample in East Africa. The results are still quite modest: people are protected against the malarial disease but not against the parasitemia and only in approximately 40% of cases. Nevertheless, these results have the merit of representing the first successful anti-malarial vaccination in man. Although great advances are still needed, a decisive step forward has been taken. Other types of vaccine will soon be tested by other groups (anti-gametocyte vaccines) and prospects of significant improvements are offered by the technique of DNA-vaccines. If it is now certain that one or several vaccines will be available in a near future, no one is able to set the time delay necessary to reach this stage. In any case, hoping that this type of vaccine will eradicate the disease is not realistic since a disease as complex as malaria, in terms of epidemiology, cannot be eliminated by only one method.(ABSTRACT TRUNCATED AT 250 WORDS)