Bedbug ID request pushes the envelope
Why did the animals/creatures of the dinosaur age grow to such an enormous size? Are the elephant and the blue whale the only examples left alive of that age? Vikram Vakil, a paleontologist doctoral candidate at the University of Queensland, responded.
It is commonly assumed that most animals from the ‘‘dinosaur age’’ grew to enormous sizes. This is far from the truth. While many nonavian dinosaurs, such as the giantnecked sauropods, did indeed attain gigantic sizes, there were many that were no bigger than a turkey.Over the years, palaeontologists have pondered over this eclectic mix of sizes that prevailed during the Mesozoic Era (‘‘middle life’’) of Earth’s geological history. A combination of factors was responsible for allowing some of the dinosaurs (specifically sauropods) to attain huge sizes.
Firstly, sauropods belonged to one of the two groups of dinosaurs (saurischians) that had a lizardlike hip bone. Saurischians had hollow bones, like birds nowadays. Birds can fly and maintain elevated temperatures and high metabolism rates, because their bones are traversed with cavities/air sacs, making their bones lightweight. Gigantic sauropods, for example, Diplodocus or Patagotitan, despite being enormous (around 80 tonnes), would still be relatively lightweight because of the pneumatic bones.
Secondly, such a lightweight skeletal framework called for a smallsized head which could easily be balanced on a long neck, thereby allowing them to reach the tops of trees, unlike most animals at that time.
Thirdly, the skulls themselves had teeth which were not specialised for chewing, allowing them to gulp in huge quantities of leaves and branches. More food means more energy, leading us to the fourth factor which is related to heat regulation.
Modern mammals and birds are ‘‘warmblooded’’, meaning they are able to generate their own body heat and maintain it. Juvenile sauropods were probably warmblooded, but it is less certain whether this was true of the adults. Their sheer size would have allowed them to stay warm, because body surface ratio and volume are inversely related to each other. A gigantic adult sauropod with its huge body had a great volume, but its surface area was comparatively small. Hence, heat retention would have been better. Dinosaurs in general tapped into every available ecological niche during their time and this was nature’s way of experimenting with beings attaining a wide array of sizes, and numerous conceivable forms, shape and colour.
By contrast, it is difficult to get so big on land with heavy, sturdy (nonpneumatic) bones. Gravity slows you down. This is why African elephants are the largest terrestrial animals alive today. Whales, living in water, are able to grow big because gravity is counterbalanced by buoyancy.
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The thought of bedbugs instils fear and revulsion in many people. Imagine my reaction when I received a letter through the post to my personal home address last week requesting that I verify the sender’s identification of the enclosed bedbugs — most of which were squashed — but some were still living, in the internal corners of the envelope and on the enclosed letter! Stains from the letter’s contents had seeped through both the back and front of the envelope, interfering with the birowritten address. This incident is one of the zany consequences of having been a longterm museum entomologist.
Bedbugs were relatively common in New Zealand during the 19th century and only disappeared in the 1950s when DDT became widely available. Bedbugs reappeared in New Zealand in the 1980s when jumbo jets and cheap air fares enabled thousands of young New Zealanders to travel to developing nations where bedbugs were endemic and rife in lowcost rental accommodation. The young travellers brought them back to university halls of residence and elsewhere, while overseas visitors already harbouring bedbugs spread their infestation to several huts on conservation ground, including national parks. There must be a problem with bedbugs in parts of
Christchurch, for that is where the envelope and its bloodsucking contents came from.
The bedbug Cimex lectularius is a true bug (order Hemiptera, suborder Heteroptera, family Cimicidae).
It is a flattened, wingless insect 6mm9mm long, brownish, becoming red after feeding. Initially, it is found in seams of clothing, beneath bed bases and mattresses, and in the space between room furniture and the wall. As they become established in a room or dwelling, bedbugs live under wallpaper, skirting boards, architraves and pictures, hiding in cracks and crevices during the day and emerging after dark to attack people sleeping in bed. The bedbug pierces the skin with its proboscis and injects an anticoagulant that produces inflamed welts and marks (often on the arm) a little larger than scratched flea bites. The female lays three to four white cylindrical eggs daily in crevices such as joints in the wood on the underside of a bed base, and can lay up to 300 eggs in her lifetime.