Chapter 1: Types of Animals
What is an animal?
-Animals are a group of organisms found on Earth
-Animals are very diverse in appearance.
-There are 4 important characteristics that all animals share:
- All animals are multicellular - they are made of many cells.
- Animals cannot make their own food. They must consume food.
- All animals require oxygen and water to survive
- All animals reproduce sexually. An offspring has two parents.
Groups of Animals
There are six major groups of animals we will study in this chapter:
- Invertebrates. Invertebrates are animals that do not have a backbone. All other animals have a backbone. They are thought to be the earliest animals that lived on Earth. Invertebrates are relatively simple animals compared to other animals. More than 95% of all animals are invertebrates. Examples: worms, jellyfish, sea stars, crustaceans, spiders, insects
- Fish. Fish are aquatic animals. They live in the water and breathe using gills. Fish do not have limbs - they have fins to help them swim and balance in water. They are the first animals to have jaws. They cannot regulate their body temperature and so they are called “cold-blooded.” Examples: tuna, salmon, sharks, rays, hagfish
- Amphibians. Amphibians are “transitional land” animals. They live in water as juveniles and on land as adults. Amphibians lay eggs in water. Young amphibians (which resemble small fish) emerge from the eggs and live in water for some time. They transform into adults that have four limbs and lungs. Like fish, amphibians are cold-blooded. Examples: frogs, toads, salamanders
- Reptiles. Reptiles are animals with dry and scaly skin. They have four limbs (or remnants of limbs) and live on land. They lay hard-shelled eggs on land. They are cold blooded and bask in the sun to stay warm. Examples: snakes, lizards, turtles, crocodiles, alligators
- Birds. Birds are animals with four limbs. The front limbs are modified into wings. Birds are covered in feathers, which help them stay warm. Birds can keep their bodies warm and so they are called warm-blooded. They lay hard-shelled eggs on land. Examples: Hawks, Owls, Parrots, Chickens, Penguins, Ducks
- Mammals. Mammals are animals that have hair and mammary glands (glands that produce milk). Nearly all mammals give birth to live young and nourish young with milk. Mammals have four limbs and are warm blooded. Examples: kangaroos, whales, horses, dogs, cats, rodents, monkeys, elephants and humans
Chapter 2: Animal Needs
What does an animal need to survive?
-In order for an animal to stay alive, it requires five important things: water, oxygen, space, food and shelter.
-Without these things, an animal cannot survive.
-Animals must survive in order to reproduce. An animal reproduces in order to make more animals. If animals do not survive and reproduce, then species of animals will die out.
Animal Needs
- Food. Animals must consume food (plants and/or other animals) in order to stay alive. Animals digest food in order to extract nutrients and energy. Nutrients are used for growth and repair in an animal. Energy is used to fuel all the processes in an animal that keep it alive.
- Water. Animals require freshwater for many reasons. Animals are mostly made of water. Without water, animals can become dehydrated and/or lose weight. Water is important to many processes that keep an animal alive. It helps digest food, circulate nutrients throughout the animal’s body and remove waste. Water helps animals regulate their body temperature as well (for animals that live in or near water)
- Oxygen. All animals require oxygen in order to survive. Oxygen is important to animals because it helps animals extract energy in food they eat. Some animals, such as fish, extract oxygen that is dissolved in water using gills. Other animals, such as reptiles, birds and mammals, extract oxygen in the air with lungs.
- Space. Animals require space or territory to obtain food, water, oxygen and shelter. Animals also require space to find mates. Animals require a partner of the opposite sex/gender in order to reproduce.
- Shelter. Animals need shelter or a place to live. Shelter provides protection from weather, such as hot sun, rain or cold wind. Shelter also protects animals from predators and other dangers.
Chapter 3: External Animal Parts
External Animal Structures
-Animals have visible structures on the outside of their bodies. These structures are called external structures because they are on the outside of animals.
-Animals have external structures that help them move, feed and sense things in the environment. They also have external structures that protect them from predators or hot/cold temperatures.
Structures Important to Movement
Animals have external structures that help them move in the environment:
-Fins. Fish have fins. Fins help fish swim or glide in the water. They also help fish balance and they help prevent fish from sinking.
-Legs. Most terrestrial (land) animals have legs. Legs help an animal walk or run on dry land. They also can help some animals swim in water.
-Tail. Some animals have a tail. A tail helps land animals balance. They help aquatic animals swim.
-Wings. Birds have modified appendages called wings. Wings help birds fly by providing “lift” as a bird moves through the air.
Structures Important to Feeding
Animals have external structures that help them eat or obtain food:
-Beak. Birds have beaks. Beaks are hard, durable and pointed structures that help birds pick up and/or crush food items. A beak can also be used to kill prey and feed young.
-Teeth. Teeth are hard structures found in the jaws of mammals, reptiles, amphibians and most fish. Teeth help animals tear apart or break food into smaller pieces.
-Mouth. Most animals have a mouth. A mouth is an opening into which the animal can consume food. It provides an entrance into an animal's digestive tract.
-Claws. Many animals, including crustaceans, insects, and some birds, mammals and reptiles, have claws. Claws are pointed appendages at the end of toes and fingers than help an animal capture prey and tear apart food.
Structures Important to Sensing Things
Animals have external structures that help them sense things in the environment:
-Ears. Many animals, including mammals, birds, amphibians and reptiles have ears. Ears help an animal hear and listen to noises in the environment.
-Tongue. Many animals, including mammals, birds, amphibians and reptiles have a tongue. A tongue a muscle in the mouth that helps an animal taste and swallow food.
-Eyes. Most animals have eyes. Eyes enable an animal to see and visualize the natural world.
-Nose. Most animals have a nose. A nose enables an animal to smell/detect odors in the environment.
Structures Important to Protection
Animals have external structures that help protect them:
-Fur. Mammals have hair or fur. Fur helps keep a mammal warm and protects it from cold weather.
-Feathers. Birds have feathers. Feathers help keep a bird warm and protects it from cold weather.
-Shell. Many invertebrates and reptiles and some mammals have a shell. A shell is a hard structure. It helps protect an animal from predators. Some animals hide in their shell when attacked.
-Horns or Tusks. Some mammals and reptiles have horns or tusks. Horns and tusks are hard, durable and pointed structures. Animals use horns/tusks to defend themselves from predators.
Chapter 4: Types of Adaptations
What is an adaptation?
-An adaptation is a trait that enables an organism to better survive in its environment.
-Adaptations can be structural or physical characteristics. Adaptations can be behaviors that improve the survival of the organism as well.
-Individuals within a species can have an adaptation. These individuals have an advantage over other individuals in their species. These individuals are more likely to survive and reproduce compared to other members of their species.
-Species as a whole can have adaptations. These species evolved to have an advantage over other species (types of organisms). These species are said to be well adapted or adapted to their environment in a specific way.
Types of Adaptations
There are two major types of adaptations:
- Physical Adaptations. Physical adaptations are physical characteristics or modifications of body parts that help an organism survive. Physical adaptations can be a body covering or body part that helps the animal better feed, move or defend itself in the environment. Physical adaptations are inherited. In other words, an organism receives its adaptation from its parents. Physical adaptations cannot be acquired by experience. Large beaks, feathers, fur and scales are adaptations that help animals better survive in the environment.
- Behavioral Adaptations. Behavioral adaptations are things an organism does that help it survive. Usually behavioral adaptations describe how an organism acts or responds to stimuli in the environment. Unlike physical adaptations, behavioral adaptations can be instinctive or learned. In other words, a behavioral adaptation can be inherited or it can be acquired through experience. How an animal moves or protects itself is a behavioral adaption. Migration and hibernation during the winter are behavioral adaptations as well.
Chapter 5: Aquatic Animal Adaptations
Aquatic Animals
-Aquatic animals are animals that live in or near water.
-All fish are aquatic animals. Amphibians are animals that live in water as a juvenile and on land (but near water) as adults. Some birds and mammals are aquatic animals that live in or near water their entire life.
-Some aquatic animals have physical structure that enable them to live in water their entire life. Other aquatic animals have modifications of body parts that enable them to successfully live near water.
Aquatic Adaptations
-Gills. Fish have structures called gills. Gills enable a fish to extract oxygen that is dissolved in water. In a way, you can think of gills as structures that enable a fish to “breathe under water.” Without gills, fish could not live in water their entire life.
-Fins. Fish have fins. Fins are structures that help a fish swim. They propel a fish through water and help a fish stay afloat by creating lift as it moves through the water. Fins also help fish balance while swimming.
-Flippers. Some mammals live in water (ex. dolphins, whales). Mammals have modified appendages called flippers. Flippers are “limbs” that help it move through water. Most aquatic mammals have two “arm flippers” and one “tail flipper.”
-Streamline Body Shape. Most aquatic animals, including fish, sea lions and whales have a streamline or sleek body shape. A streamline body shape helps an animal move smoothly through water. It reduces friction as the animal swims, which makes it easier for the animal to swim.
-Webbed Feet. Many animals that live near water, including some birds (ex. ducks, sea gulls) and amphibians (ex. frogs) have webbed feet. Webbed feet are appendages that have tissue or “webbing” between the toes. Webbed feet act like “paddles” when the animal swims through water.
Chapter 6: Feeding Adaptations
What are feeding adaptations?
-Feeding adaptations are physical and behavioral traits that help animals find, capture and eat food.
-Animals require food to live. Unlike plants, animals must obtain their food from plants and/or other animals. Without food, animals cannot survive.
-Some feeding adaptations are modifications of body parts, which allow animals to obtain and eat food items that other animals cannot eat (ex. proboscis of mosquitos and butterflies)
-Some feeding adaptations involve modifications to the digestive system. For example, some animals have multiple stomachs or secrete enzymes that allow digestion of food items that most animal cannot extract nutrients from.
Feeding Adaptations
-Teeth. Teeth are hard, calcified structures found in the mouth of mammals, reptiles, birds, amphibians and most fish. Teeth help animals tear and crush food into smaller, digestible sizes. Teeth can also help some animal capture prey.
-Beak. Birds have a hard and durable structure around their mouths called a beak. Some beaks are large and adapted for crushing hard food items such as nuts. Other beaks are small and pointy - adapted for probing into crevices for small food items such as insects and seeds.
-Claws. Some invertebrates (such as crustaceans and insects), birds, reptiles and some mammals have claws. Claws are modified appendages at the end of toes and fingers. They are hard and sharp and can be used for a variety of purposes including digging, climbing and self-defense. However, they are most often adapted for feeding. Claws help animals capture food. They also help crush and tear food into smaller, eatable pieces.
-Echolocation. Echolocation is a behavioral adaptation used by some mammals. These animals emit sound waves and listen to the echo in order to locate food. Echolocation can also be used to navigate. Echolocation is an especially important adaptation used to locate food in animals that have other senses impaired. For example, bats are nocturnal and have poor eyesight. They rely on echolocation to help them find and capture food.
Chapter 7: Locomotion Adaptations
What is locomotion?
-Locomotion is the ability to move.
-Animals must be able to move in their environment in order to find food, water and mates. Animals need food and water in order to survive. Animals need to find mates in order to reproduce and propagate (continue) their species.
-Animals also need to move in their environment in order to escape predators and other dangers.
-Some animals have physical adaptations that help them move in their environment. These adaptions help them move faster or through terrain that is difficult to move through.
Locomotion Adaptations
-Wings. Birds have wings. Wings are modified front appendages. In most birds, wings enable the organism to fly. The ability to fly gives birds an advantage over other organisms. They can easily escape predators on the ground and have a better view of the ground to more easily hunt for prey. The ability to fly also enables birds to move long distances.
-Fins. Fish have fins. Fins are structures that help fish swim. Specifically, fins propel fish through the water and they help fish stay afloat and balance while swimming.
-Hooves. Hooves are hard and durable coverings on the bottom of feet. Some mammals, including horses, goats, deer, pigs and giraffes have hooves. Hooves helps these animals walk and run, especially on uneven and rough ground. They also help with balance.
-Webbed Feet. Some birds and amphibians that live near water have webbed feet. Webbed feet are appendages with tissue (“webbing”) between the toes. Webbed feet act like paddles, helping these animals swim. The webbing makes it easier for these animals to push themselves through water. It also makes it easier for these animals to walk in mud or wet sand (which is often found near bodies of water).
Chapter 8: Body Covering Adaptations
Body Coverings
-Some animals are covered in a special substance or material called a body covering. A body covering helps protect an animal and helps it survive in its environment.
-Some body coverings are used to protect animals against temperatures in their environment. They help keep an animal warm in a cold environment or keep an animal cool or prevent water loss in a hot environment.
-Some body coverings are used to protect animals from predators. They are hard and durable and prevent predators from attacking and killing them.
Body Covering Adaptations.
-Fur. All mammals have hair. Some mammals produce thick hair called fur. Fur acts like insulation and keeps an animal warm. Sheep, bears, foxes and rabbits are just some mammals that have fur that keeps them warm in cold environments. Fur can also help a mammal camouflage or blend in with the environment in order to hide from predators.
-Feathers. Birds have feather. Feathers, like fur, help keep a bird warm. They also insulate a bird from water because they are water resistant. Furthermore, feathers help a bird fly. Feathers are lightweight, stiff and strong, which is important to being able to fly.
-Scales. Reptiles, fish and some mammals and birds have scales. Scales are small, rigid plates that grow out of an animal’s skin. They protect an animal for various purposes. Fish scales protect fish by preventing damage from sharp objects, such as coral, and predators’ sharp teeth. Reptile scales also protect reptiles and prevent damage from sharp objects. More importantly, they help prevent water loss from reptiles’ bodies in hot environments.