How Has Plants And Animals Been Selectively Bred?

Artificial selection, also known as selective breeding, is a process used in agriculture to produce desirable traits in animals and crops. It involves selecting individuals with desired traits to increase their frequency in a population. This process has been used for centuries to improve the quality of plants and animals. For example, crop plants like apples have better yields or are more resistant to different environmental conditions. Ornamental plants with particular flowers have also been created through selective breeding.

The main steps involved in selective breeding take place over many generations. In animals, the hallmark of selective breeding is small body size. For crop plants and livestock, objectives include product yield and quality. Methods for continuous traits are based on quantitative genetic principles, possibly now incorporating molecular genetic information.

Humans have been modifying the traits of plant and animal species through selective breeding for thousands of years, starting over 9,000 years ago. This practice has resulted in increased efficiency in breeding animals and plants, such as increasing milk yield. Selective plant breeding is also used in research to produce transgenic animals that breed “true” (i.e., are homozygous) for artificially inserted or deleted genes.

Selective breeding was likely the earliest form of agricultural biotechnology used by humans to improve the genetic characteristics of plants and animals. For example, plants have been selectively bred to produce larger fruits, increase resistance to pests and harsh weather, and taste better to consumers. Selective breeding does not produce the best plants or animals, but it produces the most useful plants and animals to people.

What is an example of selective breeding in animals?

Companion animals like cats, horses, rabbits, rodents, birds, reptiles, and fish have been selectively bred to be better suited for domestication and human aesthetic preferences. These animals are often bred to have variations in color and pattern or excel at specific tasks or sports. However, selective breeding in some breeds of cats and rabbits with long fur has led to increased rates of matting and skin infections, and selective breeding for stockier horses has led to bone issues. Breeders are now making strides to prevent negative health outcomes in artificially selected animals, such as avoiding inbreeding and genetic testing.

Farmed animals, such as chickens, have gotten ridiculously large since the 1950s due to selective breeding. One of the most sought-after traits by breeders is their “breast conversion rate”, or the ratio of how much breast tissue the chicken can grow compared to how much it eats. Breeders also value how fast the chickens can put on weight, with slaughter dates decreasing from 112 days to 47 in the last century.

Different lines of chickens are bred depending on whether their meat or eggs are being sold. Hens selectively bred to lay eggs often fail to meet industry standards for meat, and dairy cows are processed into other products due to inferior quality.

How has selective breeding been used by humans?

Artificial selection is a method employed in agricultural practices to cultivate desired traits in animals and crops. The method has been employed to enhance a range of foodstuffs, including meats, fruits, and vegetables such as broccoli, cauliflower, and cabbage, derived from wild mustard plants. This method is more expeditious than natural selection and enables humans to modify organisms in accordance with their requirements, rendering it an attractive option for human use.

How is selective breeding done in plants?

The process of selective breeding entails identifying and prioritizing specific traits for selection, choosing parents from a diverse population, selecting the most promising offspring with the desired traits, and repeating this cycle over multiple generations until the desired characteristics are consistently present in the next generation. This process is of great consequence for both plants and animals.

What is selection in animal breeding?

Selection is the process of selecting animals that meet breeding objectives and pass specific traits onto their offspring. It involves both subjectively measured traits (visual assessment) and objectively measured traits (genetic assessment). Visual assessment involves evaluating an animal’s conformation or shape, such as muscling, and its structure, such as overshot or undershot mouths. The requirements for selection vary depending on the enterprise’s breeding objectives.

How long have humans been selectively breeding animals and plants?

Selective breeding, an evolution by human selection, began around 10, 000 years ago after the end of the last Ice Age. Hunter-gatherers began keeping flocks and herds and cultivating cereals and other plants. This process was likely stimulated by human population pressure and environmental stress caused by rapid climate change. Global warming at the end of the Ice Age created drought in areas where rainfall had previously provided sufficient water, forcing people to congregate around reliable water sources. The increased population density favored the cultivation of plant and animal species for use during times when they were not naturally plentiful.

Selective breeding requires genetic variation on which to act, and if the variation is strictly environmentally induced, the selected variants will not be inherited by the next generation. Controlled mating is also required, making social and easily manipulated animals easier targets for selective breeding. Cultures without a strong concept of property rights, such as those of pre-Columbian South America, were less likely to domesticate species due to their difficulty segregating different breeds. A short generation time also facilitates selective breeding by speeding up the response to selection, as most plants with multiple breeds are annuals or biennials.

How does selective breeding impact plants and animals?

Selective breeding is a method of breeding animals or plants with similar genetics, resulting in a population with similar strengths and weaknesses. This process involves selecting individuals with desirable traits from a species, with the hope that their offspring will inherit those desirable traits. DNA, a specific set of information, is often used in selective breeding to create different varieties.

What are examples of in breeding in animals?

Animal mating schemes are classified into two broad categories: inbreeding and outbreeding. Inbreeding refers to mating closely related animals, such as parent and offspring, full brother and sister, or half brother and sister, while outbreeding refers to mating between less closely related animals. Inbreeding is defined as mating more closely related than the average relationship within the breed or population, while outbreeding refers to matings between animals less closely related.

The degrees of inbreeding and outbreeding are arranged according to the biological relationship between indicated mates. The classification of these mating systems is based on the closeness of the biological relationship between mates.

Why do we selectively breed plants and animals today?

Selective breeding is a method used by breeders to produce organisms with desirable characteristics, such as high crop yields, disease resistance, and high growth rate. This is achieved by crossing two members of the same species with dominant alleles for specific genes, such as long life and quick metabolism, with another organism possessing genes for fast growth and high yield. This results in a hybrid offspring, produced from two genetically dissimilar parents, which usually produces offspring with more desirable qualities.

The offspring are heterozygous, with one dominant and one recessive allele for each characteristic. Professional breeders often use a true breeding cross to create a gene bank of these qualities that can be crossed with aaBB to produce heterozygous offspring. This process of selecting parents is called artificial selection or selective breeding.

Selective breeding programs often use a small number of individuals as the “founder population” for all descendents, but there are many other genes that end up being homozygous within the small group of inbred founders. Some of these genes have deleterious effects, and their adverse conditions are disproportionately common in populations derived from a small founder group. In larger populations, cross-breeding and natural hybridization result in heterozygotes with a mutant, deleterious recessive allele masked by a normal dominant allele.

Why do people do selective breeding in animals?

Selective breeding is a method used by breeders to produce organisms with desirable characteristics, such as high crop yields, disease resistance, and high growth rate. This is achieved by crossing two members of the same species with dominant alleles for specific genes, such as long life and quick metabolism, with another organism possessing genes for fast growth and high yield. This results in a hybrid offspring, produced from two genetically dissimilar parents, which usually produces offspring with more desirable qualities.

The offspring are heterozygous, with one dominant and one recessive allele for each characteristic. Professional breeders often use a true breeding cross to create a gene bank of these qualities that can be crossed with aaBB to produce heterozygous offspring. This process of selecting parents is called artificial selection or selective breeding.

Selective breeding programs often use a small number of individuals as the “founder population” for all descendents, but there are many other genes that end up being homozygous within the small group of inbred founders. Some of these genes have deleterious effects, and their adverse conditions are disproportionately common in populations derived from a small founder group. In larger populations, cross-breeding and natural hybridization result in heterozygotes with a mutant, deleterious recessive allele masked by a normal dominant allele.

Why do humans selectively breed plants and animals?

Selective breeding is a method used by breeders to produce organisms with desirable characteristics, such as high crop yields, disease resistance, and high growth rate. This is achieved by crossing two members of the same species with dominant alleles for specific genes, such as long life and quick metabolism, with another organism possessing genes for fast growth and high yield. This results in a hybrid offspring, produced from two genetically dissimilar parents, which usually produces offspring with more desirable qualities.

The offspring are heterozygous, with one dominant and one recessive allele for each characteristic. Professional breeders often use a true breeding cross to create a gene bank of these qualities that can be crossed with aaBB to produce heterozygous offspring. This process of selecting parents is called artificial selection or selective breeding.

Selective breeding programs often use a small number of individuals as the “founder population” for all descendents, but there are many other genes that end up being homozygous within the small group of inbred founders. Some of these genes have deleterious effects, and their adverse conditions are disproportionately common in populations derived from a small founder group. In larger populations, cross-breeding and natural hybridization result in heterozygotes with a mutant, deleterious recessive allele masked by a normal dominant allele.

Is selective breeding harmful to animals?

In the animal kingdom, offspring inherit characteristics through genetic transmission, contributing to species evolution. Humans can influence this process through selective breeding, resulting in the variety of breeds we see today. However, when taken to the extreme, selective breeding can lead to the development of genetic disorders, such as severe health issues in dog breeds. Genetic disorders are health problems caused by “flaws” in an individual’s genome.

Artificial selection increases the number of genetic “flaws” and their chance of being expressed. In dogs and other pets, there is a limited number of individuals with desired traits for breeding. To bring these traits to the next generation, closely related animals or those already affected by genetic disorders are often used. This selective breeding, known as “breeding of defects”, disregards health implications and has been used for over two centuries for various purposes, including work, sport, showing, and companionship.