TOEFL® Vocabulary Flashcard

The adaptation is a change in behavior in response to new or modified environments. We often use the verbs 'develop' and 'evolve' with the word adaptation. Here are example sentences:

• Large animals that inhabit the desert have evolved a number of adaptations for reducing the effects of extreme heat. One adaptation is to be light in color and to reflect rather than absorb the Sun's rays.   
• Marine animals have developed many adaptations for surviving in marine environments. One adaptation is camouflage.
• African jackass penguins have developed unique adaptations to life in the temperate zone.
• Camels have many adaptations that allow them to live successfully in desert conditions.

Definition: Relating to bodily structure

Example sentences:

• The most remarkable of the bird's anatomical features is the feather.

To breed is to have babies. Example sentences:

• Emperor penguins breed annually during the Antarctic winter.
• The reason why emperor penguins breed during the harshest season of the year is unknown, but scientists speculate that when the chicks become independent five months later, environmental conditions are more favorable for the young birds.

The phrases “breeding ground” and “breeding season” are often used.

A breeding ground is a place where many wild animals return to the same place every year to breed.

A breeding season is a specific season of the year when animals breed.

Example sentences:

• Migratory animals migrate hundreds of miles over the course of a year, coming back to a breeding ground to reproduce and give birth to babies.
• Breeding seasons differ from species to species. The little penguin breeds throughout the year and has the shortest breeding cycle, which lasts about 50 days. Some of the temperate penguins, like the Humboldt and the African, tend to nest throughout the year.

As a noun, a brood is a group of young born at the same time — like a brood of chicks. Look a the following example sentences:

• Increased predation affects the survival of nests and broods immediately after hatching
• This nest found in a slight depression in the ground contains a brood of tiny young birds.
• While the young are in the nest, the entire brood is extremely vulnerable to predation.

As a verb, “to brood” is to incubate. To incubate means to sit on eggs to make them warm before they hatch. Example:

• In some species of birds, both the mother and father brood the eggs.
• Birds brood eggs during the incubation period to keep them protected and warm until they are ready to hatch.

Brooding is the process of incubating (brooding) eggs. Here are example sentences:

• Fossils indicate that dinosaurs might have brooding behavior.
• Birds have many adaptations to help make brooding successful and ensure a better hatch rate for eggs

Camouflage is the way in which some animals are colored and shaped so that they cannot easily be seen in their natural surroundings. For example:

• The distinctive black and white coloring of jackass penguins is a form of camouflage.
• Underwater predators looking up only see white, and predators looking down only see black.
• Many sea animals have, over time, developed different kinds of camouflage to help them blend in with their environment and avoid detection by predators.
• Sloths live high in the canopy, feeding on a wide variety of leaves and fruits. Green algae grow in the sloths’ fur, which enables it to remain camouflaged from predators. 

A carnivore is an animal that gets food from killing and eating other animals. Carnivores generally eat herbivores, but can eat omnivores, and occasionally other carnivores.

Definition: (Of biological processes) recurring naturally on a twenty-four-hour cycle, even in the absence of light fluctuations

Example sentences:

• Although caffeine's effects on alertness and sleep are well known, researchers weren't sure how it affects the circadian clock in humans.

Congregate is a verb that means to come together. The usage “congregate in groups/herds” is often used. Here are example sentences

• Penguins congregate in groups to stay warm. These group congregation facilities reproduction in extreme temperatures.
• The prey animals evolve to congregate in herds, for the protection it provides from predators, as well as the help it provides in finding food and mates.
• Buffalo congregate in larger herds to defend against attacks from predators such as lions.
• White-tailed jackrabbits are the most solitary of all the hares. However, they congregate into groups of one hundreds or more when food is abundant.

A congregation is a group of people or animals staying together.

Penguins congregate in groups to stay warm. With their group congregations, they are able to reproduce their offspring in extremely cold temperatures.

The courtship of male and female animals is their behavior before they have sex. An example in a sentence:

• The courtship of male and female animals is their behavior before they have sex.
• The ultimate purpose of courtship is to attract a receptive mate. Different courtship behaviors also serve to reduce territorial aggression.

Example sentences:

• Periodic eruptions of the volcano have destroyed 213 homes since the volcano emerged from a period of dormancy in 1983.

Definition: (Of an animal) having normal physical functions suspended or slowed down for a period of time; in or as if in a deep sleep

Example sentences:

• An animal prepares for hibernation by building up a thick layer of body fat during late summer and autumn that will provide it with energy during the dormant period. During hibernation, the animal undergoes many physiological changes, including decreased heart rate (by as much as 95%) and decreased body temperature.
• Dormant volcanoes are the volcanoes that scientists consider possible to erupt again.

Incubation periods are longer for precocial birds than for altricial birds, allowing for an increased embryonic development in the egg, and therefore they have relatively advanced motor and sensory functions at hatching.

Definition: separate and expel as waste (a substance, especially a product of metabolism)

Example sentences:

• Usually, a pregnant woman with preeclampsia develops dangerously high blood pressure and begins excreting protein in the urine.
• Earthworms ingest large quantities of soil, chemically alter it, and excrete it as organic matter called casts. The casts form an incredible natural fertilizer.
• Many microorganisms excrete methane as a waste product.

Forage has two meanings.

The first meaning is to search for food. The phrase “forage for something‘ is often used. Here are example sentences:

• Jackass penguins forage at sea and dive to a depth of 130 meters in search of food.
• The foraging behavior varies considerably among penguin species. Adélie penguins feed primarily on small krill, while chinstraps forage for large krill.

The second meaning is to eat grass.

• The cows were foraging in the pasture.

A forager is one who forages. Example sentences:

• For roughly 90% of history, humans were foragers who used simple technology to gather, fish, and hunt wild food resources. 
• Today only about a quarter million people living in marginal environments, e.g., deserts, the Arctic, and tropical forests, forage as their primary subsistence strategy. 

The adjective “foraging” describes the act of searching for food. The term “foraging behavior” is often used.

• Animals exhibit several different types of foraging behavior.​
• Scratching, a common foraging behavior for many ground-feeding birds, including sparrows, uses one foot or both feet simultaneously to remove or loosen debris from the ground to reveal seeds, bugs or other food.

Example sentences:

• The illness is believed to be caused by a defective gene. 
• Our personalities result from the complex interplay between our genes and our environment.

Definition: Of or relating to genes or heredity

Example sentences:

• Scientists believe the world’s famous fruit (banana) could disappear forever in 10 years’ time as it lacks the genetic capability to ward off pests and diseases that are in Central America, Africa and Asia.
• Bees have diminished drastically in recent years due to a variety of factors including pesticides, diseases and habitat degradation resulting in a loss of genetic diversity.
• Due to significant advances in biotechnology, experts predict that within years, doctors will be able to trace the genetic roots of common medical problems such as depression.​

Definition: by genetic mechanisms; "genetically passed down talents

Example sentences:

• Cloning is the process of making a genetically identical organism through nonsexual means

Definition: Make or become accustomed or used to something

Example sentences:

• Bears can become habituated to people very easily.

When a bird hatches, it means a bird produces young from eggs by incubation.  For example:

• The chick hatches after a month's incubation.

When an egg hatches, it means an egg opens and produces a young animal. For example:

• Once the eggs hatch, both the male and the female feed the young.

A hatchling is a young animal that has recently emerged from its egg. Here are example sentences:

• A hatchling is a young animal that has recently emerged from its egg.
• There are many obstacles for turtle hatchlings, such as crabs, birds and many other predators in the ocean.
• Young hatchlings are vulnerable to predation.

A herbivore is an animal that gets its energy from eating plants, and only plants. Omnivores can also eat parts of plants, but generally only the fruits and vegetables produced by fruit-bearing plants. Many herbivores have special digestive systems that let them digest all kinds of plants, including grasses.

Definition: determined by genetic factors and therefore able to be passed on from parents to their offspring or descendants

Example sentences:

• Scientists hope that by genetic manipulation, they will be able to cure hereditary diseases and defects.
• Cells contain hereditary information that is passed on from cell to cell during reproduction.
• Depression is often hereditary.

Example sentences:

• Diet and exercise can influence a person's weight, but heredity is also a factor.
• Identical twins tend to have similar personalities; if environment outweighs heredity in personality development, twins raised together should presumably have more similar personalities than those raised apart.

The broad definition of the verb “hibernate” is to spend the winter sleeping or resting. Hibernation is the act of hibernating, and hibernators are animals that hibernate.  Example sentences:

• Bats hibernate through the cold winter months. During hibernation, bats can survive in freezing temperatures.
• Many species hibernate during the winter, emerging only when the signs of spring promise plenty of food, telling them it is time to eat and breed again.
• Smaller animals tend to be more likely to hibernate, because migration would require an enormous amount of energy relative to their body size.

The broad definition of the verb “hibernate” is to spend the winter sleeping or resting. Hibernation is the act of hibernating, and hibernators are animals that hibernate. Example sentences:

• Bats hibernate through the cold winter months. During hibernation, bats can survive in freezing temperatures.

The broad definition of the verb “hibernate” is to spend the winter sleeping or resting. Hibernation is the act of hibernating, and hibernators are animals that hibernate.  Example sentences:

• In contrast to true hibernators such as woodchucks and hedgehogs, whose body temperatures drop close to the freezing point during the winter months, bears maintain a nearly normal body temperature throughout their prolonged sleep.

Incubate means to sit on egg in order to keep them warm before they hatch. Example sentences are:

• Birds incubate their eggs to keep them at an appropriate temperature.
• When most birds incubate eggs, the females often produce high levels of prolactin, a hormone involved in parental behavior.
• In monogamous species, both the male and female build the nest and incubate eggs.

In a laboratory, to incubate means to keep (eggs, bacteria, or embryos) at a suitable temperature so that they develop. For example:

• The embryos are incubated in the laboratory at 80°C.

Incubation is the process of incubating eggs; it also refers to the development of the embryo within the egg.

Example sentences are:

• Incubation ensures normal egg development.
• Ambient temperature is commonly thought to influence avian incubation behavior.

Another word that has the same meaning of incubation is brooding. Here are example sentences:

• Fossils indicate that dinosaurs might have brooding behavior.
• Birds have many adaptations to help make brooding successful and ensure a better hatch rate for eggs

Definition: The active immature form of an insect, especially one that differs greatly from the adult and forms the stage between egg and pupa, e.g. a caterpillar or grub

Example sentences:

• The life cycle of a butterfly includes four stages: egg, caterpillar or larva, pupa, and adult.

Definition: The active immature form of an insect

Example sentences:

• The army worms are the larval stage of a common moth.
• Animals in the larval stage will consume food to fuel their transition into the adult form.

Definition: Movement or the ability to move from one place to another

Example sentences:

• In salamanders, both swimming and ambulatory locomotion involves lateral body bending.
• Prior to 540 million years ago, organisms may have had use eyes for light sensitivity, but not for fast locomotion and navigation by vision.

Definition: A warm-blooded vertebrate animal of a class that is distinguished by the possession of hair or fur, females that secrete milk for the nourishment of the young, and (typically) the birth of live young

Example sentences:

• The domestic animal is the first mammal known to die of the disease in Europe.
• The first small mammals evolved from reptiles about 200 million years ago, and the group diversified rapidly after the extinction of the dinosaurs to become the dominant form of land animal, with around 4,000 living species.

Definition: (In an insect or amphibian) the process of transformation from an immature form to an adult form in two or more distinct stages

Example senences:

• All flies undergo complete metamorphosis with egg, larval, pupal, and adult stages in their development.

Definition: (Of an animal, typically a bird or fish) move from one region or habitat to another according to the seasons:

Example senences:

• In eastern North America, over two-thirds of breeding bird species migrate.
• Not all birds migrate, but generally speaking the more northerly the breeding ground, the more likely is it that a species will migrate south for the winter. The main reason for this annual shifting of residence is that during the northern winters food becomes scarce and the cold temperatures make survival difficult.
• Roughly half of the world’s nearly 10,000 known bird species migrate, including several songbirds and seabirds, waterfowl and waders, as well as some raptors. The Northern Hemisphere has the most diverse array of migratory birds.

Definition: Seasonal movement of animals from one region to another; Movement of people to a new area or country in order to find work or better living conditions

Example sentences:

• The extensive rural-to-urban migration has created a severe housing shortage.
• Smaller animals tend to be more likely to hibernate, because migration would require an enormous amount of energy relative to their body size.
• Populations of many migratory birds depend not only on places to breed and to spend the winter but also on the quality and continued availability of habitats along migration routes.
• Unlike animal migration, which typically involves groups of animals moving back and forth between seasonal habitats, human migration involves the movement of people who intend to leave one area for good and settle in a new one.

Definition: to copy an action

Example sentences:

• Babies mimic eating behaviors, so it's imperative that you and those regularly around your baby are exemplary food role models.
• Liquid-alternative funds mimic hedge funds by using strategies such as buying some stocks while betting against others, and investing in futures, commodities and derivatives.
• Parrots are probably most well-known for their ability to “talk,” as they can closely mimic the sounds of human voices. However, this is only seen in captive parrots. It is a mystery why wild parrots do not exhibit this behavior.

Definition: The close external resemblance of an animal or plant (or part of one) to another animal, plant, or inanimate object.

Example sentences:

• With mimicry, one organism resembles another. For example, the harmless king snake has adapted a color pattern that resembles the deadly coral snake.
• Parrots are probably most well-known for their ability to “talk,” as they can closely mimic the sounds of human voices. However, this is only seen in captive parrots. It is a mystery why wild parrots do not exhibit this behavior. It’s possible that the parrot’s relative intelligence causes it to try to bond with its owners through mimicry.

Definition: relating to the scientific study of the structure and form of animals and plants

Example sentences:

• Like animals, marine plants have both morphological, or structural, adaptations and functional adaptations.
• Many marine plants have flexible stems and leaves, which allow them to move and bend with the movement of the water around them. Some species undergo morphological change during the larva period.

Definition: relating to the scientific study of the structure and form of animals and plants

Example sentences:

• Adult crustaceans are extremely morphologically diverse.

Definition: A distinct form resulting from genetic mutation

Example sentences:

• It is important to realize that mutations in different mutant individuals are not necessarily distinct.

Definition: Symbiosis which is beneficial to both organisms involved.

Example sentences:

• One of the best-known forms of mutualism involves insects that pollinate a host plant, then deposit offspring that will ultimately consume many of the seeds. The presence of a commensal parasite that can display mutualism within a clade of known pathogens suggests dynamic evolutionary interactions.

Definition:

Example senences:

• While there may be many mutualistic relationships between plants and animals, often plants are more the victims rather than the beneficiaries of the relationship.

Definition: active at night

Example sentences:

• Most owls are nocturnal.

An omnivore is a kind of animal that eats either other animals or plants. Some omnivores will hunt and eat their food, like carnivores, eating herbivores and other omnivores. Some others are scavengers and will eat dead matter. Many will eat eggs from other animals.

Oviparous animals are animals that lay eggs, with little or no other embryonic development within the mother. This is the reproductive method of most fish, amphibians, reptiles, all birds, and the monotremes.

Definition: An organism which lives in or on another organism (its host) and benefits by deriving nutrients at the other’s expense

Example senences:

• If a species of parasite is to survive, the host organism must live long enough for the parasite to reproduce; if the host species becomes extinct, so do its parasites.
• Parasitism is a relationship where one organism, known as a parasite lives in or on another organism as a host.

Definition: (Of an organism) living as a parasite: (be parasitic on)

Example sentences:

• Mistletoe is parasitic on trees. Since viruses are parasitic on cellular life, the first life could not have been anything like a virus. Nevertheless, growing these parasitic plants in vitro is difficult, because of their dependence on a connection to hosts for normal development, and because of their specific germination requirements.
• The third type of symbiosis, mutualism, benefits both partners in the relationship. Legume plants and their nitrogen-fixing bacteria, and the interactions between flowering plants and their pollinators, are examples of mutualistic association.

Definition: the relation between two different kinds of organisms in which one receives benefits from the other by causing damage to it (usually not fatal damage)

Example senences:

• Parasitism is a relationship where one organism, known as a parasite lives in or on another organism as a host. Despite the parasite doing harm, it does not want to kill the host because the host provides nourishment but only if it is alive.

Predation is the act of preying on animals especially when you're talking about animals. Here are example sentences:

• Prey engage in myriad behaviors to avoid predation.
• Animals are vulnerable to predation.
• The predation of coyotes on deer has an adverse effect on deer populations.
• Mortality of white-tailed deer fawns is significant across the East. Predation by coyotes, black bears and bobcats account for most mortality.

A predator is an animal that eats(preys on) other animals. Predators are predatory animals.

Example sentences:

• Penguins are both predators and prey. They hunt and kill and killed and hunted by seals and sharks
• Coyotes are the top natural predator of deer.

Predatory animals are those who kill and then eat — in other words, "prey on" — other animals.

Example sentences:

• Discovery of theropod fossils indicates that many species of predatory dinosaurs had feathers.
• Hawks, lions, and alligators are all predatory animals.

Prey is an animal that is hunted or killed by another animal for food. It is an uncountable noun.

• The seals are easy prey for sharks.
• Rodents are prey for avian, reptilian, and mammalian predators.

The phrase “prey on” means to hunt and kill (something) for food. Here are example sentences:

• The wolves prey on small animals.
• Owls prey on mice.

The phrase  “fall prey to” means to be killed by (an animal, disease, etc.)

• The deer fell prey to coyotes.
• Many people fell prey to disease.

The phrase "fall prey to" can be used to describe one's vulnerability exploited by someone or something in a bad way. Look at the following example sentences

• It is very common for elderly people to fall prey to scam artists online, who take advantage of their lack of technological know-how.
• Many major cities, once thought to be untouchable by such attacks, have been falling prey to terrorist activity in recent months.

Definition: The action or process of regenerating or being regenerated;The formation of new animal or plant tissue.

Example senences:

• The treatment promotes regeneration of nerve cells in the spinal cord.
• Natural forest regeneration on deforested land exerts a controlling influence on carbon dioxide emissions. 

In biology, to reproduce is to produce offspring. Here are example sentences:

• Most animals reproduce through sexual reproduction because it increases genetic variation.
• Corals reproduce asexually by budding or fragmentation. Through budding, new polyps “bud” off from parent polyps to form new colonies. In fragmentation, an entire colony branches off to form a new colony.
• Sea anemones reproduce both sexually and asexually.

In biology, reproduction is the activity of producing offspring. Here are example sentences:

• There are two types of reproduction: asexual reproduction and sexual reproduction.
• In asexual reproduction, the offspring are genetically identical to the parent. There are many modes of asexual reproduction including budding (a new individual splits off from the parent), fission (the parent splits into two or more individuals), and fragmentation (a piece of the parent breaks off into several pieces and regenerates). Asexual reproduction has great advantages for organisms that are immobile, or unable to move around.
• The other type of reproduction is sexual reproduction, which is when new organisms are created through fertilization. Fertilization occurs when a human egg and sperm come together. Most animals reproduce through sexual reproduction because it increases genetic variation.

Anything related to reproduction can be described as reproductive. For example:

• Scientists who study reproductive habits of animals analyze how they bear offspring.
• Fertility doctors help people who are having reproductive problems.
• The reproductive behavior of fishes is remarkably diversified: they may be oviparous (lay eggs), ovoviviparous (retain the eggs in the body until they hatch), or viviparous (have a direct tissue connection with the developing embryos and give birth to live young)

Definition: (Of a cell, gland, or organ) produce and discharge (a substance):

Example senences:

• Sweat is secreted by glands in the skin when it is necessary to lose excess heat from the body.

A species is a distinct group of animals or plants that have common characteristics and can breed with each other.

Note: The word species can be singular and plural. Therefore, you can say that species is red or these species are yellow.

• More than 700 bird species breed in North America, and the variations in their behaviors are fascinating and complex. 

• The Indian elephant is a vanishing species that needs a protected habitat to survive.

Definition: Interaction between two different organisms living in close physical association, typically to the advantage of both

Example sentences:

• An example of mutual symbiosis is the relationship between sea anemones and the clownfish that dwell amongst the tentacles of sea anemones. The territorial fish protects the anemone from anemone-eating fish, and in turn the stinging tentacles of the anemone protect the clownfish from its predators.
• The third type of symbiosis, mutualism, benefits both partners in the relationship. Legume plants and their nitrogen-fixing bacteria, and the interactions between flowering plants and their pollinators, are examples of mutualistic association.

Viviparous animals are animals that give birth to young ones instead of laying eggs. This is the reproductive method of mammals except monotremes, marine mammals such as whales, dolphins, and sea otters