|The bullet ant has a very painful bite.|
----Populations and Ecosystems
----Diversity and Adaptations of Organisms
----Behavior of Organisms
Dangerous, sometimes unbelievable organisms often make the best attention grabbers for students in science class. A handful of Earth’s unusual creatures provide the backdrop for students to gain an understanding of adaptive behaviors that allow species to survive despite environmental challenges.
Students gain a greater appreciation for life science. They learn that despite unusual creatures’ often frightening behaviors, such behaviors are often adaptive and promote survival of the species within a given environment or ecosystem.
Insects, bullet ant, army ant, soldier ant, Japanese giant hornet, guinea worm, parasites, symbiotic, ecosystem, adaptation, adaptive behavior, continuation of the species, survival
Have students work in groups; each group can research an assigned creature (from among the four described below).
On Day 1, students use the provided links and/or do additional Internet research in order to take notes regarding (1) the unique characteristics of the insect or worm, (2) its key survival mechanisms, (3) how these behaviors represent an adaptation that helps them fit in well with their environment and (4) how these behaviors serve to ensure the species’ continuation.
On Day 2, students develop on large chart paper a poster that presents their findings regarding the four points above. (Teachers may opt for students to prepare PowerPoint presentations or write short essays rather than producing posters.)
On Day 3, students present their posters, PowerPoints or essays to the class. Wrap up the discussion by reinforcing the concepts of adaptation and continuation of the species.
1. Bullet Ant
Native to the rainforests from Nicaragua to Paraguay, the Bullet Ant (Paraponera clavata) is a full inch long. It lives in trees, so it will fall on you to scare you away from its hive. Before it does this, however, it shrieks at you.
It's called a bullet ant because its unusually severe sting feels like getting shot. Some of the indigenous peoples of the rainforests use bullet ants as part of an initiation-to-manhood ceremony. During the ceremony, special leaf sleeves with hundreds of bullet ants woven into them, stinger-inward, are placed on the participants’ hands. The goal is to leave them on for 10 minutes, after which the participant is allowed to rest. In order to actually become a man, however, participants have to endure the ordeal 20 times.
Survival mechanisms: Stinging, venom
2. Army Ant
Found in the Amazon Basin, huge Army or Soldier Ants (Eciton burchellii) reach a half inch in length. They possess machete-like jaws half the length of the soldiers themselves. They're notorious for dismantling any living thing in their path, regardless of size. They're also completely blind.
They're called army ants because their entire colony, comprising up to and over one million insects, is a 100 percent mobile collective. They don't make permanent hives like other ants. Rather, they stay in a single location just long enough for the queen to produce thousands of eggs, while the soldiers spread out in wide fans daily in search of food. Once the eggs hatch, the entire colony moves on to a new location.
The ants do not possess venom; they merely overwhelm any perceived threat by the hundreds of thousands and rip it apart with massive, powerful jaws. They are literally blind to size and species; the ants consider everything in their path to be a threat to the continuation of their colony. There are reports of animals the size of horses being overwhelmed and shredded by them.
When they aren’t devouring everything in their path, the ants will use their own living bodies to build any conceivable structure necessary to continue on their way. By latching on to each other foot-to-foot, the ants are able to create protective walls and ceilings against the brutal rainforest weather and bridges to cross otherwise impassable spans. There is no other living thing in the entire world that does this.
Survival mechanisms: Swarming, forming a bivouac (bridge)
3. Guinea Worm
The Guinea Worm begins life as a microscopic larva tiny enough to fit inside the common water flea, who serves as the worm’s “host.” The fleas are ingested by humans who drink from or swim in infected bodies of water.
Because the flea cannot survive in the stomach, it is digested, leaving the worm larva unharmed. The larva selects an area of the stomach and burrows in. Roughly a year after initial infection, the worm has grown to nearly three feet in length.
Because it has outgrown its environment, the worm burrows further until it reaches the skin, where it creates a blister. In a stroke of evolutionary genius, the worm causes a burning sensation in the blister. It knows that humans tend to submerge burning extremities in water. When the infected person does so, the worm pokes out from the blister and releases thousands of larvae into the water. At this point, the life cycle begins again.
Survival mechanisms: Parasitic behavior
4. Japanese Giant Hornet
Found just about everywhere in Japan, the Japanese Giant Hornet (vespa mandarinia japonica) is the size of your thumb and can spray flesh-melting poison. It targets the victim’s eyes and sprays indiscriminately with a poison that contains a pheromone. This chemical attracts other Giant Hornets to come and attack.
Few can outrun a motivated hornet, as it can fly 50 miles in a day. This results in 40 people dying from Giant Hornet attacks every year.
An adult hornet will fly miles to find food to feed to its children. Often, it finds its food in a hive inhabited by thousands of bees. The hornet sprays the nest with some of the acid/pheromone and brings in reinforcements, usually consisting of 30 or so fellow hornets. They then descend upon the beehive and proceed to kill everything. In this example, 30,000 bees are no match for 30 Giant Hornets.
Survival mechanisms: Pheromones, predatory behavior
Student presentations are evaluated in terms of the following:
Jason Tomaszewski, EducationWorld Associate Editor
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