European green woodpecker but is made sticky by secretions from the enlarged salivary glands. Heavy, prolonged snow cover makes feeding difficult for the green woodpecker and can result in high mortality, from which it may take 10 years for the population to recover. Ant nests can be located under the snow; one bird was observed to dig 85 cm to reach a nest. 'Professor Yaffle', the wooden bookend character in the 1974 children's animation series "Bagpuss", was based loosely upon the green woodpecker. 'Yaffle' was among many English folk names for the European green woodpecker relating to its laughing call; others include laughing
An Essay on the Nature and Significance of Economic Science on economic methodology in generating a range of tightly-argued, radical implications from a simple definition, for example in admitting an "aspect" of behaviour (rather than a list of behaviours) but not limiting the subject-matter of economics, provided that the influence of scarcity impinges on these (pp. 16–17). The broad behavioural definition is credited for its consistency with the expanding boundaries of economics decades later. In this Robbins both narrows the definition of economics, thereby demonstrating the usefulness of deduction, and opens up the subject-matter of economics. Robbins's "Essay" is one of the most-cited works on the methodology and philosophy of