full - FREE to download and use! (c) Oswald Skene
(Natural Science): dragonfly on green leaves OGS.jpg
D=1999-04-04 [Apr 4, 1999]; S=188kB, 661x447; T=JPEG image [MIME:image/jpeg].
Key: D= file date of exhibit; S= size in bytes, XxY pixels, etc; T= type of exhibit; L= location/time or viewpoint of exhibit (if known).
- dragonfly = dragonflies, damselfly, Odonata, Anisoptera = See the British Dragonfly Society (BDS). According to the Metro (London 20050503): "Dragonflies are amongst the fastest insects in the world, flying at speeds of up to 96kph (60mph). They have two pairs of almost equal-sized glassy wings [Anisoptera means "unequal wings"] and their compound eyes have up to 30,000 facets. The largest dragonflies have a wingspan of some 18cm, but fossils have been found with wings up to 70cm across." On the speed issue, the BDS says: "The maximum speed of large species like the hawkers is around 10-15 metres/sec, or roughly 25-30mph. Average cruising speed is probably about 10mph. Small species, and especially damselflies, are generally slower, although many medium-sized species can probably keep up with the largest ones." As to size, the BDS says: "The biggest wingspan of a living dragonfly is the Central American Megaloprepus coerulatus with a wingspan about 19cm. This is a thin, long-abdomened damselfly." ("Dragonflies and damselflies belong to the insect order known as Odonata, meaning "toothed jaw": their mouthparts are serrated. They are often referred to collectively as "dragonflies", however there are two different sub-orders.")
About This Category
This collection is of free images/photos/pictures, sounds, videos, etc from science, technology and nature, including birds, animals and plants, and some from the fields of chemistry, physics and biology. Some exhibits that could be in here may be found in collections with a more specific remit, such as "Flowers" and "Leaves and Greenery".
This is intended to serve, in part, as a teachers' and students' resource.
See also New Scientist for the latest news, The Register's science and tech stories, the EurekAlert!/AAAS Multimedia Gallery, and BioImages - Virtual Field-Guide (UK) for scholarly info.
Also, for attempts to catalogue all known species, see: the Encyclopedia of Life, and Barcode of Life.
If you're a journo or other non-scientist and need help with a science fact or story, please consider talking to Sense About Science to help you.
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