Why Do Birds False Alarm Flight?

"False alarm" mammography results--how do women react?

Most preventive care guidelines recommend that women aged 40 and older receive a mammogram every 1-2 years to screen for breast cancer. While much research has focused on the factors that influence a woman's decision to obtain a mammogram, less is known about the factors that influence a woman to return for subsequent mammograms at regular intervals. The vast majority of positive mammograms tur...

False Alarm Constrained Classification

In classification problems, the goal is often to maximize the probability of a true positive while satisfying a system design constraint on the number of false alarms. Current classifiers, which are based on minimizing classification error, achieve this goal indirectly by either shifting the bias of the resulting solution or via tuning of an asymmetry parameter. While these approaches may be us...

Evolutionary biology: Why do birds engage in extra-pair copulation?

Why do female birds mate with more than one male?

“The main hypothesis has been that the fathers of the ‘extra-pair chicks’ had especially good genes and that this was why the female had mated with them. But around the year 2000, evolutionary biologists began to doubt whether this was the main explanation. Many researchers tried to show this was the case – that is, there was a difference in genetic quality between the extra fathers and the fee...

The Flight of Birds

In a previous paper (Brown, 1948), the movements of the wing of a pigeon in slow flight were analysed. With the help of a new photographic technique further work on the flight movements at different forward velocities has been carried out. In this paper the analysis is extended with additional information obtained from normal cine-photography. Certain improvements and simplifications in the fla...