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Defenders Facts

When it comes to camouflage, the octopus makes a chameleon look like an amateur.  Its skin is covered in tiny sacs of pigment - 150,000 per square inch.  The sacs come in five colors.  When they expand or contract - the octopus changes color  like the pixels on a television screen.

When it comes to camouflage, the octopus makes a chameleon look like an amateur.  Its skin is covered in tiny sacs of pigment - 150,000 per square inch.  The sacs come in five colors.  When they expand or contract - the octopus changes color – like the pixels on a television screen. (View larger version)

Photograph by Getty Images

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  • Female Cape buffalos form large herds on the savannah, up to 1,000 strong, while males generally live on their own or in small groups.

  • Only large lion prides attempt to capture Cape buffalo, preferring to attack solitary bulls rather than herds.

  • Other than humans, African buffalo have few natural predators and are capable of defending themselves against (and sometimes killing) lions, who will attack only old, sick or immature buffalo.

  • Both sexes of the African buffalo bear horns, although their size and shape is quite variable.

  • With its large size, massive horns, and cohesive social dynamic, S. caffer is a formidable fighter.

  • The number of starlings in a roost can swell to around 100,000 in some places.

  • The benefits of flocking to prey species, whether through collective vigilance, dilution of risk, or predator confusion, depend on flock members responding in a coordinated way to attack.

  • When spooked, a collared lizard runs on all four legs, and after gaining speed, it rises up on its hind legs “like a diminutive dinosaur."

  • Horned lizard color patterns closely match the soil where they live and they can eliminate their shadows by flattening against the ground. If forced to move, a horned lizard runs only a short distance, stopping unexpectedly. The horned lizard then lies flat, disappearing from sight and the predator is left chasing nothing.

  • The Texas horned lizard has strong spine protruding from a stout bone above each eye. This structure and tough skin can save its life.

  • To the uninitiated, their dragon-like appearance is quite formidable. The squat form and head armour has given rise to the name "horny-toad," "horned toad" and "horned lizards."

  • Blood-squirting is also an odd and interesting behavior that eight species of horned lizards are known to use effectively to deter a specific group of predators – canids (e.g., dogs, foxes and coyotes). When blood comes in contact with a canid’s mouth, the predator shakes its head in obvious protest to the taste. If the predator is holding the lizard in its mouth, it drops it, affording the lizard a chance to escape. This defense must come at quite a cost because many individuals exhibit it only after going through a complete repertoire of other defensive behaviors.

  • The primitive hagfish – also known as the snot-eel. Hagfishes (Myxinidae), a family of jawless marine pre-vertebrates, hold a unique evolutionary position, sharing a joint ancestor with the entire vertebrate lineage. They are thought to fulfil primarily the ecological niche of scavengers in the deep ocean.

  • Hagfishes are commonly considered to feed exclusively by opportunistic scavenging, having been observed primarily feeding on carrion falls or discards from fisheries, and having also been caught in large numbers in baited traps. Hagfishes may also exploit prey captured by other organisms, such as sea stars and crabs.

  • The mouth lacks jaws, but a hagfish is equipped with two pairs of tooth-like rasps on the top of a tongue-like projection. As this tongue is pulled back into the hagfish's mouth, the pairs of rasps pinch together. This bite is used to tear into the flesh of dead and dying fish which have sunk to the muddy ocean bottom, or in catching and eating marine invertebrates.

  • Hagfishes are notorious for their ability produce large volumes of slime when they are provoked or stressed. Hagfish slime differs from other animal slimes in that it contains not only slippery mucins, but also fine fibres, or ‘slime threads’, which are believed to lend it strength and cohesion. The slime is formed when specialized slime glands eject coiled threads (or ‘skeins’) and mucin vesicles into seawater.

  • The tarantula's appearance is worse than its bite. Tarantula venom is weaker than that of a honeybee and, though painful, is virtually harmless to humans.

  • Coatis were observed rolling the prey item between their paws before consuming the item during 11.7% of the samples and it was likely that the coatis were consuming millipedes and tarantulas during these samples.

  • If forced to defend itself, the arachnid may flick very fine, fiber-glasslike, sharp, barbed hairs from its abdomen at its enemy (shown in the images below). These may stimulate ocular, dermatologic, and respiratory tract irritation. Density of hairs on the abdomen is approximately 10,000 per mm2.

  • The uniqueness of the rattle and its related shaker muscles have prompted a variety of hypotheses concerning the rattle’s evolution, the most widely accepted theory is that this appendage evolved as a signal to warn enemies about the rattlesnake’s venomousness.

  • Cobras are recognized by the hoods that they flare when angry or disturbed; the hoods are created by the extension of the ribs behind the cobras' heads. These reptiles are found throughout the Philippines, southern Asia, and Africa.

  • To achieve such dead-on spitting, the researchers discovered in high-speed video that the snakes cheat a bit. They shake their head rapidly while spraying the toxin - increasing the area that gets struck.

  • Most of the 1,100 species possess an asymmetrical abdomen which is concealed in an empty gastropod shell that is carried around by the hermit crab.

  • This design is to enable the hermit to occupy an empty spiral shell as a temporary refuge, and protection. I say temporary because as the hermit crab grows larger, shells also need to be larger for continued occupation. This house hunting must be a complicated business for hermits, for they have also to undergo the normal crustacean moulting period as well.

  • Hermit crab anemone Calliactis Miriam. Mutualistic symbiosis with hermit crabs of the genera Dardanus and Eupagurus. The crab attaches the anemone on its shell, and takes advantage of the stinging cells protection. The anemone benefit is probably the greater possibility to find food, being transported. When the crab changes shell, it transfers the anemones on the new one.

  • A number of animals are associated with this hermit crab, particularly the sea anemone Calliactis parasitica, which lives on the shell of the hermit crab, and provides increased protection against predators, receiving improved food collection in return. This is known as a symbiotic relationship, as both parties benefit from the association.

  • The perennial honeybee colony is a very attractive resource for parasites, predators and especially for conspecific, inter-colonial honey-robbery.

  • Guard bees are specialized on this task of discrimination and are more likely to attack non-nest mates than are other task groups.

  • Bees protect their nests using a variety of defense strategies.

  • The termite queen becomes an “egg-laying machine” and may produce as many as 36,000 eggs a day for many years.

  • The sterile workers live for 2-4 years while primary sexuals live for at least 20 and perhaps 50 years.

  • The primary function of the soldier caste is defense. Since most termite soldiers are blind, they probably locate enemies through tactile and chemical means.

  • Termite workers were largely defenseless and passive in fights with the ants.

  • The termite society, or colony, is a highly organized and integrated unit. There is a caste system with division of labour based on the colony members’ structure, function, and behaviour. The major castes in the colony are the reproductive, soldier, and worker castes. Soldiers and workers are sterile and may be male or female. The functional reproductives are of two types, referred to as primary and secondary, or supplementary.

  • The most highly developed cephalopods are the octopuses. They have eight arms. They are predators feared in the sea, because they can see very well (they have highly developed eyes like the vertebrates) and also very highly developed behavioural patterns.

  • The cephalopods (meaning ‘head-footed) are a group of molluscs that contain the octopuses, squid and cuttlefish, and are probably the most intelligent of all invertebrates. They have well-developed heads, with large complex eyes and mouths that feature beak-like jaws. All octopuses have eight tentacle-like arms; indeed ‘octopus’ derives from the Greek for ‘eight-footed’.

  • Octopuses, squid and cuttlefish are probably the most adept camouflage artists in the animal kingdom.

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