Adaptive advantages of the compound leaf form in flowering plants have so far remained elusive. A novel idea—proposed here—is that there are no direct advan-tages; the compound leaf evolved instead as a trade-off of selection in favour of something else: greater leafing intensity. Producing more

Latitudinal variation in the asynchrony of seasons: implications for higher rates of population differentiation and speciation in the tropics

A hypothesis to explain host species differences in resistance to multi-host parasites

In East and Central Africa, the nymphalid butterflies Danaus chrysippus, Acraea encedon and A. encedana are involved in a Müllerian mimicry complex. Unusually for aposematic mimetic organisms, the three species show extensive colour pattern polymorphism. Within the same geographic zone, the three species show female-biased sex ratios as a consequence of infection by maternally-inherited, male-killing bacteria. The co-occurrence of biased sex ratios and aposematic polymorphism within these three sympatric, mimetic butterfly species has led to the speculation that invasion by the male-killing bacteria and the subsequent female-biased sex ratios are the underlying reason for the maintenance of colour polymorphism in these species,

Fishing for significance in phylogenies: too many alternatives for the same outcome, or an appeal to Journal editors

highly influential events

We have witnessed great interest and a wealth of promise in content-based image retrieval as an emerging technology. While the last decade laid foundation to such promise, it also paved the way for a large number of new techniques and systems, got many new people involved, and triggered stronger

We study how early stage new ideas are turned into successful businesses. Even promising ideas can be unprofitable if they fail on one dimension, such as technical feasibility, correspondence to market demand, legality, or patentability. To screen good ideas the entrepreneur needs to hire experts

“Somebody says, ‘You know, you people always say that space is continuous. How do you know when you get to a small enough dimension that there really are enough points in between, that it isn’t just a lot of dots separated by little distances? ’ Or they say, ‘You know those quantum mechanical amplitudes you told me about, they’re so complicated and absurd, what makes you think those are right? Maybe they aren’t right. ’ Such remarks are obvious and are perfectly clear to anybody who is working on this problem. It does not do any good to point this out.” —Richard Feynman [1, p.161]

Two kinds of contemporary developments in cryptography are examined. Widening applications of teleprocessing have given rise to a need for new types of cryptographic systems, which minimize the need for secure key distribution channels and supply the equivalent of a written signature. This paper