Black and Yellow Cranefly

With the warm temperatures of the last few days, I leave my office window open, and insects get in at night. This morning, arriving to work I found this cranefly, likely Nephrotoma flavipalpis, recognisable by the dark spot towards the end of its wings and mostly yellow head. Its bulbous - as opposed to pointy - abdomen indicates it is a male. He landed on the box of the Concise Edition of BWP, which provided a suitable white background, although the leg of a flamingo is visible in the photo below.

Crane Fly halteres

This Crane Fly or Daddy Long Legs (possibly Tipula scripta) got into the house and I gave a try to getting its portrait on a white background. It is pleasantly surprising how many insects that I expect to fly away immediately do actually stay still through my white bowl session. The little knobbed structures sticking out at the sides of the body are the halteres, typical of all flies but more prominent in these large flies. They evolved from the hindwings and when in flight move in opposite directions as the wings and are involved in balancing and steering and contribute to the exquisite flying abilities in the group, although crane flies themselves are weak, wobbly fliers

Celebrity flies

Continuing with the topical apple subject, I have been leaving damaged and rotten apples on the soil of a large pot. The place now is heaving with tiny fruit flies of the genus Drosophila - possibly the most famous and best known fly in biology, D. melanogaster. It is difficult to give an idea of how much research has been carried out using this fly but a quick search on the Google Scholar academic search engine yielded today under 3,000 hits on the common earwig, while D. melanogaster had 324,000 entries. Since the beginning of last century, experiments on fruit flies have generated much of the basic knowledge of genetics and evolution, and their genome sequence was published in 2000, before the human genome. Among the many reasons they have become such a popular model organism is that they are ubiquitous, easy to keep (who doesn't have fruit flies around the compost heap or fruit bowl?) and reproduce rapidly producing many eggs.
Much research has been carried out on fruit flies mating behaviour and the influence of genes on it. Despite their tiny size fruit flies can be easily watched performing their mating rituals on top of the rotting apples. Males are smaller and with a larger dark patch at the end of their abdomen. Females have a more stripy, and often distended abdomen.
According to Marla Sokolowski:

It might come as a surprise to some that D. melanogaster shows many exquisitely performed and complex patterns of behaviour. For example, the male fly shows courtship behaviour that is full of sensory stimuli and that requires the female to hear his song, feel his taps and licks, smell his odours and visually evaluate his stature...

As a primer, this figure (also from Sokolowski, 2001) illustrates the main steps of the fruit fly mating behaviour. Male 'song' is produced by wing vibration while keeping the wing tipped forward.

Check out the Drosophila melanogaster Wikipedia page for more info.