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Poison dart frog
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The poison dart frog is the common name given to the most poisonous animals on Earth. Native to Central and South America, these species of frogs (family: Dendrobatidae) produce several lethal toxins that are capable of killing a human or other large animal with just 2 micrograms (μg). In other words, one drop of their venom could be powerful enough to kill 8000 people. The most toxic of poison dart frog species is Phyllobates terribilis. Unlike snakes, dart frogs do not synthesize their poisons, but sequester the chemicals they consume from arthropod prey, such as ants, centipedes and mites. This is why in captivity, they produce far less poison than wild frogs due to their change in diet. What makes these frogs immune to their own poison i ...
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1531 |
bio_man |
6 years ago |
What are the most poisonous plants?
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Plants are essential for any ecosystem, being both a food source and habitat for living things. Although plants are stationary, many are dangerous to touch or eat, making you sick or cause a bad reaction. Some of the most poisonous plants are described below: Abrus Precarious or Rosary Pea (Left) This plant has beans that contain a deadly poison. Ironically, their seeds are often used in jewelry and rosary making, but are not harmful when touched, only if chewed or scratched. The poison is known to stop protein synthesis, leading to organ failure. Ricinus Communis or the Castor Bean (Center) The castor bean plant comes from Africa and its seed is the source of castor oil used all over the world. However, the seeds contain a deadly poison called ...
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10567 |
bio_man |
7 years ago |
World's deadliest tree
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The manchineel tree ( Hippomane mancinella) has taken the title of world’s most dangerous tree. This evergreen grows up to 15 metres (49 ft) tall, and is native to tropical southern North America and northern South America. It has reddish-greyish bark, small greenish-yellow flowers, and shiny green leaves ranging in size from 5 to 10 cm (2–4 inches) long. All parts of the tree contain strong toxins, some unidentified. The leaves and fruit of the tree superficially resemble an apple tree, however one bite of the tree’s fruit can cause abdominal pain, vomiting, bleeding, or death due to an acetylcholine inhibitor known as physostigmine found in the fruit. In addition, its milky white sap contains phorbol and other skin irritants, producing s ...
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4267 |
duddy |
8 years ago |
What makes bats 'tick'
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Bats have an uncanny ability to track and eat insects on the fly with incredible accuracy. But some moths make these agile mammals miss their mark. Tiger moths (left), for example, emit ultrasonic clicks that jam bat radar. Now, scientists have shown that hawk moths (right) and other species have also evolved this behavior. The nocturnal insects - which are toxic to bats - issue an ultrasonic "warning" whenever a bat is near. After a few nibbles, the bat learns to avoid the noxious species altogether. Interestingly, the sound-producing apparatus is typically located at the tip of the moth's genitals. ...
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12818 |
duddy |
8 years ago |
Stay away from the castor bean
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Some organisms, such as the castor bean plant ( Ricinus communis), produce substances that inhibit the synthesis of proteins (called translation) within a cell. (The plant, which is native to Africa, is not related to the species of bean plants with which you are likely more familiar.) A protein called ricin, produced within the castor seeds is an extremely potent inhibitor of protein synthesis. In fact, it is one of the strongest natural toxins produced. A single chewed seed can kill child! If the ricin were purified, it would take an amount equivalent to only a few grains of salt to kill an adult. Ricin kills cells by enzymatically cleaving covalent bonds within the large and small ribosomal subunits, rendering the protein-building factori ...
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20219 |
savio |
8 years ago |
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3488 |
duddy |
9 years ago |
Hammerhead shark or worm?
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The hammerhead worm is a master of regeneration. Cut one into eight pieces, and you'll get seven new hammerhead worms. Twice a month they'll reproduce by deliberately sticking their tails to the ground, pulling them off, and that tail will become a new hammerhead worm.
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3460 |
duddy |
10 years ago |
A woolly insect
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It is not surprising that this family of moths are commonly called woolly bears or woolly worms, as the caterpillars of many species are really very hairy. The larvae can be full of poisonous chemicals acquired from their host plants, advertising that they are bad to eat with bright colours, bad odours and unusual shapes. The adult moths have distinctive wing venation and can also be distasteful when eaten. They produce ultrasonic sounds to warn off predators and confuse bats looking for a tasty treat. There are over 10,000 species worldwide including all the tiger, footmen, wasp and lichen moths. Amazingly, the caterpillars of some species can even survive freezing. ...
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4024 |
savio |
10 years ago |
My new favourite animal
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Meet the guineafowl puffer ( Arothron meleagris), all puffed-up and poisonous to deter any would-be predators. Found throughout the Indo-Pacific and Eastern Pacific Oceans, this spotty species loves feeding on tiny marine invertebrates and the tips of coral.
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7584 |
duddy |
10 years ago |
Pixelated snake
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This is the Green vine snake ( Ahaetulla nasuta), a slender tree snake found in India, Sri Lanka, Bangladesh, Burma, Thailand, Cambodia and Vietnam. The snake is mildly venomous, and its bite causes swelling and pain. They feed on frogs and lizards. There is a widespread myth in parts of southern India that the species uses its pointed head to blind its human victims!
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10009 |
duddy |
10 years ago |
The Bushveld rain frog
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The Bushveld rain frog is found in Southern Africa. When threatened, it puffs itself up to ward off potential attackers. The frogs are sexually dimorphic, and the male is too small to mount the female properly to reproduce. The white secretion you see on the back of the frog is actually an adhesive that holds the male in place during copulation.
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3581 |
savio |
11 years ago |
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