Barnacles parasitize the large oblique snout crab: A male large oblique snout crab is parasitized by a parasitic barnacles and becomes female. The crab's large claws no longer develop and their abdomen widens, providing a place for barnacles to be raised. Thousands of barnacles are hatched by crabs and then spread to seawater, infecting other crabs.
When parasitic trematodes reproduce asexually in snails, their larvae find tadpoles from American bullfrogs, burrow into its skin, and form sacs around the developing limbs of the bullfrog. As a result, bullfrogs have more and more deformed feet, making them easy to become food for birds such as herons.
The female pink butterfly plate velvet cocoon bee is a parasitic wasp that can inject dozens of eggs into the larvae of the large butterfly. After these eggs hatch, the larvae feed on the internal tissues of the caterpillar until they emerge from the surface of the body. They paralyze caterpillars and form small yellow cocoons.
Cordyceps serpentine fungi are true "brain suckers", and when their spores fall on ants, they burrow into the exoskeleton of the latter, enter the brain, and drive it away from its habitat on the forest floor and climb to a nearby tree.
Canopy ants feed their larvae with bird droppings. Sometimes, bird droppings contain parasitic nematodes, and when ants eat this nematode, the abdomen will turn bright red, like a ripe berry, thus attracting birds to come and peck. Through this process, parasitic nematodes can be spread far away. They also prompt ants to their abdomen as they walk, making them easier to spot with birds.
When ladybird cocoons sting ladybirds, they leave an egg inside the ladybird. After the eggs hatch, the developing larvae eat the ladybird's tissue from the inside out, while avoiding harm to key organs and keeping the host from dying. After the cocoon bee larvae burrow out of the ladybird, they form a cocoon between the ladybird's legs.
Parasitic wasps prey on a silver-bellied spider and lay their eggs on the spider's abdomen. After the eggs hatch, the larvae burrow holes in the spider's abdomen and feed on the spider's body fluids. When the larva pupates, they cause the spider to tear off its own web and form a completely different new web, with only a few crossed silk threads forming a cocoon that is only used to protect the larvae.
Clematis enter the house crickets while they feed on insect carcasses and then grow inside. House crickets are terrestrial, but adult clematis need to live in water. So when the clematis is fully developed, it changes the cricket's brain to travel to the nearest body of water, where it burrows out of the house cricket's body.