Shifting Paradigms in the Mechanics of Nectar Extraction and Hummingbird Bill Morphology.

As functional morphologists, we aim to connect structures, mechanisms, and emergent higher-scale phenomena (e.g., behavior), with the ulterior motive of addressing evolutionary patterns. The fit between flowers and hummingbird bills has long been used as an example of impressive co-evolution, and hence hummingbirds' foraging behavior and ecological associations have been the subject of intense study. To date, models of hummingbird foraging have been based on the almost two-centuries-old assumption that capillary rise loads nectar into hummingbird tongue grooves. Furthermore, the role of the bill in the drinking process has been overlooked, instead considering it as the mere vehicle with which to traverse the corolla and access the nectar chamber. As a scientific community, we have been making incorrect assumptions about the basic aspects of how hummingbirds extract nectar from flowers. In this article, we summarize recent advances on drinking biomechanics, morphological and ecological patterns, and selective forces involved in the shaping of the hummingbird feeding apparatus, and also address its modifications in a previously unexpected context, namely conspecific and heterospecific fighting. We explore questions such as: how do the mechanics of feeding define the limits and adaptive consequences of foraging behaviors? Which are the selective forces that drive bill and tongue shape, and associated sexually dimorphic traits? And finally, what are the proximate and ultimate causes of their foraging strategies, including exploitative and interference competition? Increasing our knowledge of morphology, mechanics, and diversity of hummingbird feeding structures will have implications for understanding the ecology and evolution of these remarkable animals.

Determination of soil adhesion to plastic surfaces using a radioactive tracer.

A quantitative radiochemical test procedure was developed for investigating soil adhesion on polyvinyl chloride (PVC) model materials containing different plasticizers (DOP and Hexamoll) and commercial flooring materials. A repeatable test procedure was developed, including soiling and cleaning with a Mini Cleanability Tester. Three soils all containing 51Cr emitting gamma radiation were used. The materials were subjected to successive soiling and cleaning cycles in order to generate soil accumulation. The type and amount of plasticizer appeared to affect soil adhesion on plastic model materials.

Early results of the Finnish Multicentre Study of Prostatic Cancer (Finnprostate).

Four hundred and four prostatic cancer patients diagnosed in the years 1979-1982 in nine Finnish hospitals have been followed up for a mean period of three years. The aim of this study is to evaluate the situation of this malignancy in the Finnish male population and to discuss the diagnostic procedures and treatment modalities. In one fifth of the patients the carcinoma was as incidental finding on microscopical examination of tissue removed by transurethral resection or enucleation for presumed benign prostatic hyperplasia. At the diagnostic moment 69% of the tumours were locally advanced beyond the prostatic capsule and one third of all cases had metastasized. 134 out of 404 (33%) have died and 45% of these of prostatic cancer. Survival was adversely affected by the tumour differentiation grade. In non-metastasized cases the local extent of the tumour had no notable effect on prognosis. Some early comparisons are made between orchidectomy and oestrogen therapy.