What is cartilage?

Cartilage is smooth elastic tissue, such as the human rib cage, ear, and nose.

Cartilage does not contain blood vessels or nerves.

Sharks, rays, and skates are cartilaginous fish because they have a skeleton made entirely of cartilage.


What is biofilm?

Biofilm is a slimy bacterial mico-organism that sticks to a living or non-living surface.

Dental plaque on animal or human teeth is biofilm.

Biofilm can be a single species or a group of micro-organism that form a biological system, like a community.  

Biofilm can be found everywhere, all over the globe, even in extreme climates, such as glaciers. Mostly, it is foud on rocks and pebbles on the bottom of stagnant and still rivers and streams.

Fish and aquatic animals love to eat biofilm.

One foot, two feet …

What is an animal with one foot, two feet, three feet …?

An appendage, such as a foot or a leg, is used for locomotion – walking, moving, or running.

Ped or pod means foot (leg) or feet (legs).

A mollusk, such as a snail or a slug, is an example of an animal with one foot. It is a gastropod – it is a body of one piece. Gastropod means stomach foot.

An animal that walks with two feet is a biped. A bird is a biped.

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Rainfall Patterns: how much is too much rain?

Rainfall is called precipitation. Rain is freshwater, not saltwater.

Precipitation includes rain, drizzle, sleet, snow, graupel, and hail. It is water vapour that condenses and falls to earth. (Mist and fog are not precipitation because they do not fall; the moisture remains in a cloud near the ground).

A little bit of very small drops of rain that falls very gently is called drizzle.

A little bit of rain that falls steadily is called a rain shower.

Rain with small ice pellets is called sleet.

Rain with heavy and large ice pellets is called hail.

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What are grasslands?

Grasslands are areas where the vegetation is mainly grasses, rushes, bulrushes, and sedges, as well as legumes, clover, and other herbs.

Grasslands occur naturally on all continents except Antarctica.

Grasslands are herbaceous swamps, meadows, parklands, pastures, prairies, savannahs, sedge swamps, and steppes.

Grasslands can have very short grass or very long grass.

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What is the jaw strength of the Hyena?

The Spotted Hyena (Crocuta crocuta) is a scavenging carnivorous African mammal. It has one of the strongest bite strengths of any mammal due to its strong jaws.

A dog, for example, such as a Mastiff or Rottweiler, has an average bite strength of 325 pounds per square inch. An African Lion has a bite strength of 650 pounds per square inch. A Bengal Tiger has a bite strength of 1,050 pounds per square inch. The Spotted Hyena has a bite strength of 1,100 pounds per square inch.

A Great White Shark has an average bite strength of 625 pounds per square inch. A Hippopotamus has an average bite strength of 1,825 pounds per square inch. The animal with the strongest bite strength is the crocodile at 3,700 pounds per square inch.

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What is the difference between a chrysalis, a cocoon, and a pupa?

What is the difference between a chrysalis, a cocoon and a pupa?

A chrysalis is the pupal casing of butterflies. A butterfly caterpillar pupates into a chrysalis, and an adult butterfly emerges.

A cocoon is the pupal casing made of moths and other insect larvae. A moth caterpillar pupates into a cocoon, and an adult moth emerges.

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Unwanted Animals

Unwanted plants are called weeds, obnoxious plants, or invasive species. What are unwanted animals called?

Unwanted animals are called vermin, pests, strays, parasites, or invasive species when they are considered to be harmful or destructive to people, other animals, plants, or crops.

For example, fleas are often referred to as parasitic, and rats are considered to be vermin because both carry disease.

Human-introduced animals in a region, which become harmful to the native species and the ecosystem, such as the goats on Galapagos Island, are called invasive species.

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How do ungulates clean their hooves?

Ungulates are hoofed animals such as horses, donkeys, zebras, camels, giraffes, and deer. Hooves can be single (such as a horse’s hoof) or cloven (split into two parts). Deer, cattle, sheep, and goats have cloven hooves.

A hoof is the tip of a toe of an ungulate. It is made of keratin, a thick, hard covering. The sole of the hoof is partially rubbery, but hardens near the outer edges. There is also a hard wall formed by the solid nail rolled around the tip of the toe.

Humans keep animal’s hooves clean and trimmed. In the wild, animals have natural ways of keeping their hooves healthy.

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Animal Ears: do big animals have big ears?

Do big animals have big ears and small animals have small ears? No, animal ears are many sizes and shapes.

Most ears have an outer ear (a pinna, a canal, and an eardrum), a middle ear, and an inner ear.

The pinna is the fleshy part that is visible. It is made of cartilage, not bone, so it is soft. It usually also has an ear lobe. The pinna directs sound through the canal to the eardrum.

The pinna has a muscle that moves the ear. For example, elephants and dogs can move their ears. Animals move their ears in the direction of a sound so that they can hear better.

Not all animals can move their ears because they have weak and non-functioning ear muscles. Animals that cannot move their ears include gorillas and monkeys. Humans cannot move their ears (without touching them).

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Hierarchical Aggression in Baboons

Baboons live in hierarchical groups, called troops, with dominant members, usually males. A troop is 5-250 individuals, with the usual group having about 50 individuals.

The Savannah Baboon, or Yellow Baboon (Papio cynocephalus), from eastern Africa, is an example of a baboon population that lives in a hierarchical social group.

Hierarchical aggression, or dominance hierarchy, in baboons is a form of communication to secure territory, to determine which members eat and drink first, or to determine breeding dominance.

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