A Grey parrot (Psittacus erithacus), able to quantify 6 or fewer item sets (including heterogeneous subsets) by using English labels (I. M. Pepperberg, 1994), was tested on addition of quantities involving 0-6. He was, without explicit training, asked, "How many total X?" for 2 sequentially presented collections (e.g., of variously sized jelly beans or nuts) and required to answer with a vocal ...

Over the years, the African continent has had to battle several outbreaks of infectious diseases in different countries. Some of the most deadly were the Ebola virus disease (EVD) outbreaks that occurred in West Africa between 2014 and 2016 affecting Guinea, Liberia, and Sierra Leone and, more recently, from 2018 to 2020 in the Democratic Republic of Congo (DRC). In the era of the COVID-19 pand...

How do we measure avian ‘intelligence’ and communicative capacities? Two decades of study on Grey parrots (Psittacus erithacus) provide more questions than answers. What is intelligence? Can we evaluate nonhumans using human tasks and definitions? Or fairly test nonhuman sensory systems? How do nonmammalian brains process information? Do avian and mammalian cognitive capacities significantly ov...

CONTEXT Congo red is the essential histologic stain for demonstrating the presence of amyloidosis in fixed tissues. To the best of my knowledge, nothing has been written about why the stain is named "Congo." OBJECTIVE To understand the etymology and history of the Congo red histologic stain. DESIGN Primary sources were consulted extensively, including 19th-century corporate documents, newsp...

To investigate the epidemiology of human African trypanosomiasis (sleeping sickness) in Kinshasa, Democratic Republic of Congo, 2 entomologic surveys were conducted in 2005. Trypanosoma brucei gambiense and human-blood meals were found in tsetse fly midguts, which suggested active disease transmission. Vector control should be used to improve human African trypanosomiasis control efforts.