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W L Oliver

Publications and source records attributed to W L Oliver.

6 recordsLinked to original sources

Detecting letters in continuous text: effects of display size.

In three letter detection experiments, subjects responded to each instance of the letter t in continuous text typed in a standard paragraph, typed with one to four words per line, or shown for a fixed duration on a computer screen either one or four words at a time. In the multiword and the standard paragraph conditions, errors were greatest and latencies longest on the word the when it was correctly spelled. This effect was diminished or reversed in the one-word conditions. These findings support a set of unitization hypotheses about the reading process, according to which subjects do not process the constituent letters of a word once that word has been identified unless no other word is in view.

Attention

Population and troop ranges of Lemur catta and Lemur fulvus at Berenty, Madagascar: 1980 census.

The November 1980 census suggests that population size and troop ranges have remained stable since 1972 and in a small area since 1963. This prolongs the apparent stability described by some authors, remarkable in a 200-ha reserve containing a maximum of 300 Lemur catta. However, inadvertent introduction of Lemur fulvus rufus and apparent loss of tamarind trees, as well as general genetic and biogeographic considerations, imply this stability may not continue. Berently underlines the need for long-term, widespread primate research and practical conversation.

Animals

Propithecus verreauxi population and ranging at Berenty, Madagascar, 1975 and 1980.

Propithecus verreauxi have been repeatedly censused in parts of the 200-ha reserve at Berenty between 1963 and 1975. Troop rearrangements in 1963 and 1975 showed that both males and females can change troop outside the breeding season. Group sex ratio varies from 0.3 female/male to 5.0 female/male. Usually, at Berenty, groups defend highly exclusive territories, in contrast to ranging patterns elsewhere. In 1980 troops were censused during 2 weeks in November at a different season from earlier studies. They had larger troop feeding dispersion than before, and pairs and triplets of males who travelled apart from bisexual troops. This may be a season of mass male migration, as in Lemur catta, or else a long-term population change. This small reserve should be carefully monitored as its lemurs have so far maintained relative population stability.

Animals