Did You Know? Christmas Special

Here are 10 fun facts about animals associated with Christmas.

Do you know which one is not true?

1. Reindeer (Rangifer tarandus) (also known as caribou). Some populations in North America  migrate the farthest of any terrestrial mammal. In a year they can travel up to 5,000km (3,000 miles), covering 100,000,000 km2 (400,000 square miles). To put that into perspective, that’s like travelling from Land’s End to John O’Groat’s almost six times over and covering an area almost twice the size of France.

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Reindeer (Rangifer tarandus). By Alexandre Buisse.

 

2. Donkey (Equus africanus asinus). Donkeys are often kept in fields with nervous horses because they seem to have a calming effect on them. If a donkey is introduced to a mare and a foal, the foal will often turn to the donkey for support once it has left its mother.

3. Polar bear (Ursus maritimus). Polar bears have such a good sense of smell that they can detect seals buried under 3 feet of snow from 1 mile away. When sprinting, they can reach speeds of up to 25 mph. They are also excellent swimmers, using large paws for propulsion while body fat provides buoyancy.

4. European robin (Erithacus rubecula). Robins use vision-based magnetoreception to sense the magnetic field of the Earth as a navigational ‘compass’.

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European robin (Erithacus rubecula). By Francis C. Franklin.

5. Penguins (family Spheniscidae). One species, the chinstrap penguin (Pygoscelis antarctica), was featured in an episode of the BBC’s Planet Earth II. Millions of these penguins congregate on the remote Zavadovski Island, 1,300 miles east of the Falklands, at the foot of its huge active volcano. Adults risk their lives every day foraging for fish in the stormy seas to feed themselves and their chicks.

6. European turtle dove (Streptopelia turtur). This migratory species is listed as Vulnerable on the IUCN Red List due to habitat loss, droughts/climate change, hunting and competition with other doves. In Europe’s Common Birds 2007 report, the turtle dove population in Europe had fallen by 62% in recent times.

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European turtle dove (Streptopelia turtur). By Yuvalr.

7. Oxen are cattle (Bos taurus) trained as draft animals (e.g. in pulling ploughs and carts). In 2009, a publication in Science reported the mapped bovine genome, showing that cattle share about 80% of our genes and share about 1000 genes with dogs and rodents.

8. House mouse (Mus musculus). Mice eat their own faeces to acquire nutrients produced by bacteria in their intestines. Like most rodents, they do not vomit.

9. Arctic fox (Vulpes lagopus). They hibernate in underground tunnels for six months in the cold winter, using their fat reserves to keep them alive until they emerge in spring.

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Arctic fox (Vulpes lagopus). By Mr Per Harald Olsen.

10. Camels (family Camelidae). The male dromedary camel has an organ in its throat called a dulla, which is a large inflatable sac he extrudes from his mouth when rutting to exert his dominance over other males and to attract females. Camels have humps that store reservoirs of fatty tissue – avoiding the extra layer of insulation over their entire bodies in their hot and dry habitats.

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Dromedary camel (Camelus dromedarius). By Jjron.
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The Leafy Sea Dragon – Did You Know?

In my Did You Know series, learn some fun facts about an animal in 5 minutes. I’ll tell you stuff you didn’t already know (hopefully). Let me know if I surprised you!

Today I’ll tantalise your curiosity taste buds with a master of masquerade: the leafy sea dragon.

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The leafy seadragon or Glauert’s seadragon, Phycodurus eques. Photo credit: James Rosindell

Did You Know?

  • It is a species of fish named after the dragons described in Chinese mythology and folklore (and more recently in George R. R Martin’s Game of Thrones)
  • It is the only member of the Phycodurus genus in the Syngnathidae family of fishes.
  • Its resemblance to a piece of drifting seaweed may help to protect it from predators. Its seaweed-like appearance not only allows it to match the background of seaweed and kelp it lives amongst (making it very hard for predators to spot), but it may also serve as a type of camouflage called ‘masquerade’. This is when an animal tricks its predator into thinking it’s an inedible object that isn’t dinner, similarly to that seen in leaf and stick insects. If you’re interested, you can read more about masquerade here and here.
  • Another aspect of this ‘floating seaweed’ trick seems to be the sea dragon’s sedate movement through the water. It moves at a slow rate of about 150m per hour propelled by fins along the side of its head but often stays in the same place for long periods of time.

 

 

  • Unusually in the animal kingdom, the male is the sole responsible parent. The female deposits 150-250 bright pink eggs onto the male’s tail, and then leaves him to it. He carries them in a honeycomb-like structure called the brood patch for 8 weeks where they are supplied with oxygen until the young emerge (like its relatives: seahorses, pipefish and other sea dragons). Only about 5% of the eggs survive and the young are completely independent at birth.
  • It feeds exclusively on small crustaceans like mysid shrimp.
  • Their natural habitat is calm, cold water (10-12 degrees Celsius) in the southern coasts of Australia, where they are known locally as ‘leafies’.
  • It is classified as Near Threatened by the IUCN Red List 2006, and may even be reclassified as Endangered, mainly due to habitat loss and pollution through human activity.
  • It has been protected by the Australian government since 1982 and is the marine emblem for the state of South Australia.

Thanks for reading and look out for other posts in my Did You Know? series!

The Platypus – Did You Know?

In my new Did You Know blog series, learn 10 facts about one animal in 5 minutes. In the series, I’ll tell you stuff you didn’t already know (hopefully). Let me know how many surprised you!

Today I’m going to blow your mind about an ancient mammal: the duck-billed platypus.

Did You Know that platypuses…

1. …Are one of only five mammal species that lay eggs instead of giving birth to live young (Monotremes). The other four are species of echidna. The eggs develop internally for 28 days and are incubated externally for 10 days. The platypus genome has both reptilian and mammalian genes associated with egg fertilisation.

2. …Are one of very few venomous mammals. The male has a spur on the hind leg that can cause severe pain in humans.

3. …Is a recognisable and iconic symbol of Australia. It is endemic to eastern Australia, including Tasmania, and appears on the reverse side of the Australian 20-cent coin.

4. …Completely stunned European naturalists when it was first discovered in 1798. The specimen of a bizarre duck-billed, beaver-tailed, egg-laying mammal was first thought a hoax.

5. …Is the only type of mammal (except some dolphins) to use electroreception. Monotremes (platypuses and the four echidna species) can locate their crustacean prey by sensing the electric fields caused by their muscle movements. A sheet of electroreceptors is found on the bill. By shaking its head from side-to-side while swimming it can detect differences in signal strength to sense the direction of the electrical source.

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The platypus (Ornithorhynchus anatinus) is one of the world’s most primitive mammals. John Gould print image: Wikipedia Commons.

6. …Closes its eyes, ears and nose when it hunts underwater. Solely relying on electroreception and sense of touch (mechanoreceptors) on the bill, prey are found by detecting both the electrical fields and mechanical pressure pulses they emit. The different arrival times of these two signals to the bill signify the distance to the prey.

7. …Have unusual eyes among mammals. Their poor vision is more similar to Pacific hagfish than to other tetrapods (vertebrates higher than fishes) and the eyes contain double cones involved in luminance (brightness) perception, which most mammals do not have. Although vision may have been important for hunting in distant ancestors, this may have been sacrificed for the electrosensory system that is better suited to an aquatic and nocturnal lifestyle.

8. …Have a unique swimming motion among mammals. Webbed feet propel them through the water, although only the front feet are used for power in an alternate rowing motion; the hind feet and tail are used for steering.

9. …Feed their young with milk released through pores in the skin. Although platypuses have mammary glands – one of the defining features of a mammal – they lack teats. Instead the blind, helpless and naked young drink milk that pools in grooves on the mother’s abdomen.

10. …Are descended from the extinct monotreme Steropodon.  The fossilised specimen is thought to be about 110 million years old, making it the oldest mammal fossil to be found in Australia. Another fossil relative, Monotrematum sudamericanum, can be placed in the supercontinent Gondwana (when Antarctica joined Australia and South America) up to about 167 million years ago.

Feel free to make suggestions about other animals you want to see featured in the series!

Great White Sharks – Did You Know?

In my new Did You Know blog series, learn 10 fun facts about one animal in 5 minutes. In the series, I’ll tell you stuff you didn’t already know (hopefully). Let me know how many surprised you!

Today I’m focusing on one deadly predator: the great white shark.

Did You Know that great white sharks…

1. …Have serrated teeth. When feeding, they shake their head from side to side so the teeth can tear off large hunks of flesh.

2. …Are known to attack and kill people. This may not come as much of a surprise, given Peter Benchley’s best-selling novel “Jaws” and the popular gory 1975 film adaptation by Steven Spielberg. Most shark attacks on humans appear to come from great whites. But despite its deadly reputation, shark researchers say out of all the prey great whites attack they rarely attack and kill humans.

3. …Have an extra sense organ. Ampullae of Lorenzini in sharks’ skin allow them to detect the electromagnetic field emitted by the movement of living animals. This has led to the development of electric-emitting deterrents to prevent attacks on people.

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The great white shark (Carcharodon carcharias). Wikipedia Commons.

4. …Can change their core body temperature. Cooler blood in the arteries is heated up by warmer blood in the veins to heat core temperature, helping them to chase agile and fast prey like sea lions. Core temperature can also be reduced to conserve energy.

5. …Rely on their liver for long-distance migrations. Fat and oil stores in their livers help provide energy during long migrations through nutrient-poor waters.

6. …Are pretty huge. Females can reach a length of 16 feet (almost 5 metres). That’s two and a half Michael Jordans laid end-to-end. Some 20 ft monsters have been recorded.

 

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Size comparison between a human and a typical great white. Wikipedia Commons.

7. …Have a massive bite force of 669 pounds per square inch (18,000 newtons) revealed by computer models. But, relative to other animals like polar bears, snapping turtles, and killer whales, this is actually rather wimpy. Perhaps this is because they can rely on their serrated teeth as predatory weapons, rather than just on the power of their jaws.

8. …Are one of few sharks known to use ‘spy-hopping’. This involves poking their head above the sea surface to look at other objects in the water, such as prey.

9. …Are highly opportunistic ambush predators likened to human serial killers. When hunting seals, great whites breach the water surface due to the momentum of their high speed pursuit (see the breathtaking slow-motion video of this happening in BBC Planet Earth).

10. …Can be killed and eaten by killer whales (orcas). When the two competing species meet, orcas have been known to suffocate sharks by pinning them upside-down to then eat their liver.

Feel free to make suggestions about other animals you want to see featured in the series!

Octopuses – Did You Know?

In my new Did You Know blog series, learn 10 fun facts about one animal in 5 minutes. In the series, I’ll tell you stuff you didn’t already know (hopefully). Let me know how many surprised you! Let’s start off with one soft-bodied cephalopod: the octopus. 

Did You Know that octopuses…

1. …Have three hearts. Yup! One pumps blood through the body (systemic) and the other two pump blood through each of the two gills (branchial).

2. …Have a relatively short life expectancy. Some smaller species live for only 6 months.

3. …Can die from reproduction. Females can die of starvation after their eggs hatch (they don’t eat while they take care of unhatched eggs), and males can die immediately or a few months after mating. Sexual unhealing.

4. …Can kill a person. The blue-ringed octopus bite is so toxic it can kill you within minutes. Not a great choice for a pet.

5. …Usually have no internal skeleton. The only hard part of their body is the beak (except in octopuses of the Cirrina order, which have an internal shell).

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The greater blue-ringed octopus (Hapalochlaena lunulata). Wikipedia Commons. Blue-ringed octopuses are known to be one of the world’s most venomous marine animals.

6. …Have a beak that helps them squeeze through very narrow gaps when escaping from predators like moray eels and predatory fish.

7. …Have eight arms with suction cups that are highly touch-sensitive. The suction cups help them sense many aspects of their environment, such as recognising other octopusessurface curvature and shape, and taste.

8. …May eject viscous ink when they feel threatened. Inking in cephalopods acts as a defence by distracting and deterring predators, provides a smokescreen to hide behind, and causes sensory confusion in predators, such as by mimicking the smell of food.

9. …Are highly intelligent among invertebrates. They are quick to solve problems and some have been known to use tools, reflecting their superior cognitive abilities.

10. …Can change colour in a matter of seconds or minutes to match or mimic their environment for camouflage against predators, to flash a warning signal, and to signal to other octopuses.

Feel free to make suggestions about other animals you want to see featured in the series!