Name: Artificial Selection: Visualization in Plants and Data Analysis - Concept
Uploaded: 2019-01-29T11:04:44.000Z
Duration: 3 min 14 s
Channel: JoVE

K12 Standards

north-carolina-k-12-science-standard-course-of-study

North Carolina K-12 Science Standard Course of Study

9-12

Biology

Biological Evolution- Unity and Diversity

LS.Bio.9.1

Artificial Selection

lab manual sub articles

Lab Manual Sub Articles

<p>When you look at a population of animals you may notice some variations or differences between individuals of the same species. Perhaps some are larger than others or there are differences in their coloration. These variations serve as the basis for natural selection where beneficial traits in a population that positively affect survival and reproduction will be preserved. For example, animals that can more easily camouflage with their environment evade predators and pass on their genes more often than those that do not. This camouflage coloration is a phenotype, defined as the visual expression of a trait. A genotype refers to the set of genes responsible for a phenotype. Therefore, due to natural selection certain genotypes are maintained over time, while less favorable variations disappear and this drives the evolution of populations. </p>
<p>We humans have studied this process and taken advantage of naturally occurring variations to purposely evolve plants and animals to farm or keep as companions. This process is known as artificial selection, the propagation and domestication of plants and animals for favorable traits. Let&#39;s look at dogs for example. Thousands of years ago, humans started selectively breeding pairs of wolves for traits like docility, protection and hunting prowess along with appearance. We continued this selective breeding over countless generations and this has culminated in scores of modern dog breeds, including the Great Dane and Chihuahua, which in turn are both very different in appearance and character to their ancestor, the wolf. </p>
<p>We have also implemented artificial selection in plants. <em>Brassica oleracea</em> was once a large, leafy plant, but it has been artificially selected in different ways to produce many common vegetables we eat today, including kale, cabbage, cauliflower and even kohlrabi. Another species in the same family, <em>Brassica napus</em>, is commonly known as the oilseed rape plant because of the abundant oil sequestered in its seeds, which are excellent for cooking or fuel production.</p>
<p>In this lab, you will artificially select traits from individual oil seed rape plants to produce two lines displaying different levels of a trait, hairiness.<br />
 </p>

artificial selection

<h4>Natural Selection and Adaptive Evolution</h4>
<p>In natural settings, adaptive evolution takes place by natural selection, a process in which differences in traits lead to differences in survival and reproductive success between individuals. This happens because individuals with certain phenotypes have a higher probability of survival and/or produce more surviving offspring than individuals with other phenotypes. <br />
A classic example of this was demonstrated by Rosemary and Peter Grant studying the population of Medium Ground Finches on Daphne Major Island, in the Galapagos archipelago<sup>1</sup>. In the late 1970&#8217;s, the islands experienced a drought during which few plants flowered and produced seeds. The birds were forced to survive on large, thick shelled seeds left over from previous years.  Of the population, only the birds with larger beaks could harvest efficiently. As a consequence, birds with small beaks died; the few birds that survived were larger and had thicker, stronger bills. These differences in bill size were genetic, and therefore heritable, so the offspring produced the following year had, on average, larger bill and body sizes than had been present in the population before the drought.  Interestingly, 8 years later there was particularly high rainfall, resulting in a resurgence of small seed producing plants.  The small beaked finches were observed to be more abundant in subsequent years.  Indeed, over the past 5 decades, this finch population has oscillated in accordance with the food type available<sup>1,2</sup>.<br />
More generally, natural selection leads to evolution of populations, because populations contain genetic variation that results in expression of different phenotypes. In the case of the finches, the birds present in the population before the drought varied in bill size and these differences in turn affected the size of seeds each individual was best able to eat. Without such variation, evolution cannot happen because there is no variation for selection to act upon.</p>
<h4>Artificial Selection and Domestication of Plants and Animals</h4>
<p>Humans have taken advantage of natural variation to create a wide variety of domesticated plants and animals through artificial selection, also known as selective breeding. In this case, humans cause selection because they select which phenotypes of animal will breed to produce the next generation. Artificial selection has been used for much of human history to produce crops and animals that are more efficient or have desirable traits, such as plants that produce larger fruits and vegetables, or cows that produce more milk.<br />
If selection is applied consistently for many generations, it is possible to produce an organism that hardly resembles the one it originated from. Dogs as diverse as Chihuahuas and Great Danes were derived from gray wolves in a few thousand years. This rate of change tells us that much of the genetic variation necessary to produce these domestic breeds was present in the population of wolves originally descended from.  Researchers are studying the genetics of modern breeds of dogs to determine what genetic elements differ between them that might be correlated with their obvious differences in appearance and even behavior.  This may then serve as a good model for understanding human genetic diversity<sup>3</sup>.<br />
Artificial selection in plants can clearly be seen in the diversity of cruciferous vegetable crops derived from <em>Brassica olaracea</em>, a large leafy plant native to coastal southern and Western Europe. It has been bred by human populations in multiple locations, over hundreds of years, to produce an estimated 400 different vegetables, such as turnips, cabbage, kale, broccoli, cauliflower, and Brussels sprouts<sup>4</sup>.<br />
Researchers, as well as farmers, have taken advantage of another species in the same genus, <em>B. rapus</em>, a subspecies of which has been bred to have an extremely short life cycle of about one month. This variety is known as &#8220;Wisconsin Fast Plants,&#8221; <sup>5</sup> and is used as a model organism in research and education. <em>B. rapus</em> germinates in a few days, produces flowers after two weeks, and produces viable seeds by the end of four weeks. The plant generally dies at the end of this cycle.</p>
<h4>References:</h4>
<ol class="references">
	<li>Rosemary B. Grant, Peter R. Grant; What Darwin&#39;s Finches Can Teach Us about the Evolutionary Origin and Regulation of Biodiversity, BioScience, Volume 53, Issue 10, 1 October 2003, Pages 965&#8211;975, https://doi.org/10.1641/0006-3568(2003)053[0965:WDFCTU]2.0.CO;2</li>
	<li>Weiner, Jonathan. The Beak of the Finch. Penguin Random House. May 30, 1995 | 352 Pages</li>
	<li>Wayne RK1, Ostrander EA. Lessons learned from the dog genome. Trends Genet. 2007 Nov;23(11):557-67. Epub 2007 Oct 25. PMID: 17963975 DOI: 10.1016/j.tig.2007.08.013</li>
	<li>J.W. Fahey, BRASSICAS, Editor(s): Benjamin Caballero, Encyclopedia of Food Sciences and Nutrition (Second Edition), Academic Press, 2003, Pages 606-615, ISBN 9780122270550, https://doi.org/10.1016/B0-12-227055-X/00118-8. (http://www.sciencedirect.com/science/article/pii/B012227055X001188)</li>
	<li><a target="__blank" href="https://fastplants.org">https://fastplants.org/</a> Retrieved August 21, 2018</li>
</ol>

Artificial Selection: Visualization in Plants and Data Analysis - Concept

Natural Selection and Adaptive Evolution
In natural settings, adaptive evolution takes place by natural selection, a process in which differences in ...

Education

JoVE Lab Manual

Evolution

natural selection

Natural Selection

Fitness
Widespread variation of phenotypes in natural populations provides the raw material for evolution, which is the change in the inherited traits of ...

hardy-weinberg and genetic drift

Hardy-Weinberg and Genetic Drift

Evolutionary change is interesting and important to study, but changes in populations occur over long periods of time and in huge physical spaces and are ...

evolutionary relationships

Evolutionary Relationships

Humans have been attempting to properly classify living things since Aristotle made the first attempt during the 4th century BC. Aristotle&#8217;s system ...

plant diversity

Plant Diversity

From Water to Land
Kingdom Plantae first appeared about 410 million years ago as green algae transitioned from water to land. Though challenging, this ...

animal diversity

Animal Diversity

Kingdom Animalia is composed of a range of organisms united by a set of common characteristics. Barring a few exceptions, animals are multicellular ...

microbial and fungal diversity

Microbial and Fungal Diversity

Bacteria and fungi are two highly diverse groups of organisms that can have significant beneficial or detrimental impacts on human health. For this ...

evolution

Learn how selective breeding shapes dogs and crops, from wolf ancestry and Brassica vegetables to Wisconsin Fast Plants and their rapid life cycle.

Selective Breeding in Dogs and Crops | JoVE K12

LS.Bio.9.4

Pennsylvania State Academic Standards

Life Science

Natural Selection and Evolution

3.1.9-12.U

3.1.9-12.W

Louisiana Student Standards for Science

High School

Life Sciences

Biological Evolution: Unity And Diversity

HS-LS4-2

ohios-learning-standards-and-model-curriculum

Ohio’s Learning Standards and Model Curriculum

Mechanisms

Virginia  Standards of Learning

HIgh School

BIO.7

BIO.7.c

Minnesota Academic Standards in Science

3.2.1 9L.3.2.1.4

4.1.1 9L.3.2.1.5

new-jersey-student-learning-standards-for-science

New Jersey Student Learning Standards for Science

Biological Evolution: Unity and Diversity

HS-LS4-4

Arizona Science Standards

HS+B.L4

HS+B.L4U1.14

Alabama Course of Study Science

Unity and Diversity

9-12.B.4.14

Next Generation Science Standards

heredity-inheritance-and-variation-of-traits

Heredity: Inheritance and Variation of Traits

HS-LS3-3

HS-LS4-3

HS-LS4-5

Florida Department of Education

SC.912.L.15

SC.912.L.15.13

Texas Essential Knowledge and Skills

BIO.10

BIO.10.B

south-carolina-college-and-career-ready-science-standards

South Carolina College and Career Ready Science Standards

B-LS4-2.

B-LS4-3.

new-york-state-science-learning-standards

New York State Science Learning Standards

Inheritance and Variation of Traits

HS-LS3-3.

HS-LS4-3.

HS-LS4-4.

HS-LS4-5.

Georgia Standards of Excellence

Ecology

SEC2.

SEC2.c

SB6.e

Learn how to prepare pots, plant Brassica seeds, and care for seedlings with light and watering before an artificial selection experiment.

Growing Brassica for Selection Experiments | JoVE K12

Explore how artificial selection changes plant hairiness by counting trichomes, breeding high and low hairiness lines, and comparing generation data.

Plant Breeding by Trichome Count | JoVE K12

<ul><li><a href="#" data-time="0.0">Observing Artificial Selection in Plants
</a></li></ul>

<ol class="note-items"><li data-note-item="1" data-parent-collapse="">Observing Artificial Selection in Plants
<button class="expand">Expand</button><ul class="lab-items"><li data-sub-note-item="1-1"><div class="lab-step">Two weeks before beginning the pollination experiments, collect a sufficient amount of small pots with a drainage hole in the bottom of each pot. 
</div></li><li data-sub-note-item="1-2"><div class="lab-step">Fill each pot about halfway with moist potting soil.  NOTE: It is recommended to use a minimum of 50 plants for generation one. It is standard practice to list the species name and date of planting on each individual pot, although this is not necessary to label the generation one plants.
</div></li><li data-sub-note-item="1-3"><div class="lab-step">Add a fertilizer pellet to the surface of the soil and then add more soil to the pot, enough to cover the pellet. 
</div></li><li data-sub-note-item="1-4"><div class="lab-step">Use a dissecting probe to make a shallow &#188; inch depression in the surface of the soil. 
</div></li><li data-sub-note-item="1-5"><div class="lab-step">Then, touch a toothpick tip to a glue stick. Use the sticky end of the toothpick to pick up one of the Brassica seeds and place the seed into the depression in the soil.  NOTE: The dissecting probe can be used to knock the seed off the toothpick as needed.
</div></li><li data-sub-note-item="1-6"><div class="lab-step">Lightly cover the seed with a thin later of soil.  Then, repeat steps 3 &#8211; 6 for each pot.
</div></li><li data-sub-note-item="1-7"><div class="lab-step">Place the pots in a brightly lit area, such as near a south-facing window or under a grow light.  NOTE: Ensure the light is uniformly distributed across the group of plans. If this is not possible, rotate the plants every few days to ensure equal exposure.
</div></li><li data-sub-note-item="1-8"><div class="lab-step">Water the plants with a plastic dropper until a small amount drains out of the pot. Do this as frequently as necessary to keep the soil moist.
</div></li></ul></li></ol>

<div class="section-question"><h4 class="question-sect">What is natural selection?</h4><p>Natural selection describes the process where variations in traits differentially affect survival and reproductive success between individuals in natural settings.
</p></div><div class="section-question"><h4 class="question-sect">What is required for natural selection to occur?</h4><p>For natural selection to occur, phenotypes in a population must be variable, heritable, and result in variation in fitness of organisms.
</p></div><div class="section-question"><h4 class="question-sect">How does natural selection lead to evolution?</h4><p>Populations of a species contain genetic variations that are passed down among generations. These differences allow certain individuals to fare better in survival and/or reproduction.
</p></div><div class="section-question"><h4 class="question-sect">What is artificial selection?</h4><p>By adapting the concept of natural selection, humans have created a variety of domesticated plants and animals by selecting favorable traits.
</p></div><div class="section-question"><h4 class="question-sect">How have we benefited from artificial selection?</h4><p>Many of the crops and domesticated animals we keep today are an outcome of artificial selection. Artificial selection has enabled us to produce crops and animals more efficiently.
</p></div>

Artificial Selection: Visualization in Plants and Data Analysis - Prep

Observing Artificial Selection in Plants
ExpandTwo weeks before beginning the pollination experiments, collect a sufficient amount of small pots with a ...

<p>Two weeks before beginning the pollination experiments, collect a sufficient amount of small pots with a drainage hole in the bottom of each pot, and then fill each pot about halfway with moist potting soil. Here, the procedure is demonstrated with five plants. However, it is recommended to use a minimum of 50 plants for generation one.</p><p>Although it is not necessary to label the first generation, it is standard practice to list the species name and date of planting on each individual pot. Add a fertilizer pellet to the surface of the soil and then add more soil, enough to cover the pellet. Next, use a dissecting probe to make a shallow 1/4 inch depression in the surface of the soil.</p><p>Then touch a toothpick tip to a glue stick. Use the sticky end of the toothpick to pick up one of the brassica seeds and place the seed into the depression in the soil, using the dissecting probe to knock the seed off of the toothpick, as necessary. Lightly cover the seed with a thin layer of soil and place the pots in a brightly lit area, like in a south-facing window, or under a grow light.</p><p>Make sure that the light is uniformly distributed across the group of plants. If uniform light isn't possible, rotate the plants every few days to ensure that they all have equal exposure. Finally, use a plastic dropper as frequently as necessary to add water until a small amount drains out of the bottom of the pot to keep the soil moist.</p><p>Please take time to review the material list and the student protocol video to be fully prepped for the lab.</p>

<ul><li><a href="#" data-time="0.0">Observing Artificial Selection in Plants 
</a></li><li><a href="#" data-time="290">Data Analysis
</a></li></ul>

<ol class="note-items"><li data-note-item="1" data-parent-collapse="">Observing Artificial Selection in Plants 
<button class="expand">Expand</button><ul class="lab-items"><li data-sub-note-item="1-1"><div class="lab-step">To begin the experiment, collect five two-week old grown plants from the generation one population that appear healthy. Note: Plants should appear green, not wilted, and not have damaged leaves. Experimental Hypothesis: The experimental hypothesis for this lab might be that the number of lead trichomes varies naturally, but the average number will increase over generations if only plants with the highest number of trichomes are interbred or decrease if those with the least are interbred. Null Hypothesis: The null hypothesis might be that the average number of trichomes will not change over subsequent generations after artificial selection.
</div></li><li data-sub-note-item="1-2"><div class="lab-step">Label each plant with a letter from A to E and with both partners&#8217; names.
</div></li><li data-sub-note-item="1-3"><div class="lab-step">Record any natural differences you see between your plant samples. Note: All of the plants are the same age, so any observed variation is due to expressed phenotype, not development.
</div></li><li data-sub-note-item="1-4"><div class="lab-step">Use a hand lens to count the number of trichomes found on the petiole of the lowest leaf, not including the round, first-grown cotyledons for each plant. Note: It can be helpful to shine a light onto the plant and to hold it against a dark background, such as a lab bench, during the trichome analysis. 
</div></li><li data-sub-note-item="1-5"><div class="lab-step">Both partners will conduct counts on each plant independently and compare answers. If the counts are different, enlist a third counter or take the average of the two results.
</div></li><li data-sub-note-item="1-6"><div class="lab-step">After this, determine the median number of trichomes for the entire class.  <a target="__blank" style="display:block;padding:20px;" href="https://www.jove.com/CDNSource/lm/labs/2/Lab_2_Table_A.xlsx">Click Here to download Table A</a>
</div></li><li data-sub-note-item="1-7"><div class="lab-step">Determine the top and bottom 10% of the plants from the class trichome count. These groups will make up the two artificially selected lines: high hairiness and low hairiness, respectively.
</div></li><li data-sub-note-item="1-8"><div class="lab-step">If more than 10% of the plants have no trichomes, select 10% of those plants randomly for the low hairiness plant line.
</div></li><li data-sub-note-item="1-9"><div class="lab-step">Separate the two groups of selected plants and label them clearly.
</div></li><li data-sub-note-item="1-10"><div class="lab-step">Move the plants to a well-lit area and keep them well watered until they develop flowers. Note: Flowers typically develop around 14 days.
</div></li><li data-sub-note-item="1-11"><div class="lab-step">When the flowers are fully developed, use a pollination wand or paintbrush to rub the stigma and anther of one plant&#8217;s flowers for a few seconds.
</div></li><li data-sub-note-item="1-12"><div class="lab-step">Using the same wand or brush, rub the inside of each flower of every other plant in the same selection line.
</div></li><li data-sub-note-item="1-13"><div class="lab-step">Using a different wand or brush, repeat steps 11 through 12 on the other line. Note: Take care not to cross the lines. Spread the pollen only among the appropriately selected plants.
</div></li><li data-sub-note-item="1-14"><div class="lab-step">Return the generation one plants to the growing areas. When the plants reach approximately 1 month old, they should produce mature seed pods.
</div></li><li data-sub-note-item="1-15"><div class="lab-step">Allow the plants to dry out once the seed pods turn yellow.
</div></li><li data-sub-note-item="1-16"><div class="lab-step">Break the seed pods open and collect the seeds.
</div></li><li data-sub-note-item="1-17"><div class="lab-step">Obtain new pots for the generation two seeds.
</div></li><li data-sub-note-item="1-18"><div class="lab-step">Fill the pots with moist potting soil about halfway and add a fertilizer pellet to each pot.
</div></li><li data-sub-note-item="1-19"><div class="lab-step">Fill the pots with more soil to fill just below the lip.
</div></li><li data-sub-note-item="1-20"><div class="lab-step">Make a shallow depression in the soil of each pot with a probe.
</div></li><li data-sub-note-item="1-21"><div class="lab-step">Touch a clean toothpick to a gluestick and use the toothpick to transplant the seeds into the soil one by one.
</div></li><li data-sub-note-item="1-22"><div class="lab-step">Cover the seeds with a thin layer of soil.
</div></li><li data-sub-note-item="1-23"><div class="lab-step">Label the pots with their hairiness line and place them in the designated growing area.
</div></li><li data-sub-note-item="1-24"><div class="lab-step">Use a plastic dropper to water the plants as needed to ensure they do not dry out.
</div></li><li data-sub-note-item="1-25"><div class="lab-step">When the plants are two weeks old, collect five plants from each line and label them A to E.
</div></li><li data-sub-note-item="1-26"><div class="lab-step">Then, count the trichomes on these plants as previously described (steps 4- 5).
<a target="__blank" style="display:block;padding:20px;" href="https://www.jove.com/CDNSource/lm/labs/2/Lab_2_Table_B.xlsx">Click Here to download Table B</a>
</div></li></ul></li><li data-note-item="2" data-parent-collapse="">Data Analysis
<button class="expand">Expand</button><ul class="lab-items"><li data-sub-note-item="2-1"><div class="lab-step">Create a frequency graph based on the generation one class data with the trichome count on the x axis and the number of plants on the y axis. Label the mean. 
</div></li><li data-sub-note-item="2-2"><div class="lab-step">Then, create frequency graphs for both of the selected hairiness lines.
</div></li><li data-sub-note-item="2-3"><div class="lab-step">Compare the frequency graphs for generation one and both hairiness lines.
</div></li><li data-sub-note-item="2-4"><div class="lab-step">Take note of phenotypic shifts observed in the selected hairiness lines.
</div></li></ul></li></ol>

Artificial Selection: Visualization in Plants and Data Analysis - Procedure

Observing Artificial Selection in Plants 
ExpandTo begin the experiment, collect five two-week old grown plants from the generation one population that ...

<p>To begin the experiment, collect five two-week old grown plants from the generation one population that appear healthy. That is, plants that are green, not wilted, and do not have damaged leaves. The experimental hypothesis for this lab is that the number of leaf trichomes varies naturally, but the average number will increase over generations if only plants with the highest number of trichomes are interbred or decrease if those with the least are interbred.</p><p>The null hypothesis is that the average number of trichomes will not change over subsequent generations after artificial selection. Label each plant with a letter from A to E and with both partner's names. Record any natural differences you see between your plant samples.</p><p>All of the plants should be the same age, so this variation is due to expressed phenotype, not development. Using a hand lens, count the number to trichomes found on the petiole of the lowest leaf, not including the round, first-grown cotyledons for each plant. It can be helpful to shine a light onto the plant and to hold it against a dark background, such as a lab bench, during the trichome analysis.</p><p>To ensure accuracy, both partners should conduct the counts independently, and compare answers. If the counts are different, enlist a third counter, or take the average of the two results. Record the agreed upon counts in the table and report the data to your instructor for compilation.</p><p>When all of the data has been compiled, determine the median number of trichomes for the entire class. To create two different lines of artificially-selected plants from generation one, determine the top and bottom 10%of the plants from the class trichome count. These plants will be called the high hairiness and the low hairiness lines, respectively.</p><p>For the low hairiness line, it is possible that more than 10%of the plants counted will have no trichomes. If this is the case in your experiment, select 10%of plants randomly for the low trichome group for the low hairiness plant line. Separate the two groups of selected plants and label them clearly, then move all of the plants into a well-lit area and keep the plants well watered until the develop flowers, which is typically and around 14 days old.</p><p>When the plants produce fully developed flowers, each student should take a pollination wand or paintbrush and rub it gently against the anther and stigma of one plant's flowers for a few seconds. Then, rub the same brush inside each flower of every other plant in the same selection line. Using a new wand, repeat the pollination for each plant until all of the plants have been pollinated.</p><p>Being careful not to cross the lines and to spread the pollen only among the appropriately selected plants. Then place them back into the growing area. When the generation one plants are approximately one month old, they should have produced mature seed pods.</p><p>Allow the plants to dry out once the seed pods begin to turn yellow. Next, remove the seed pods from each plant. Break open the seed pods and collect new empty pods to plant the seeds.</p><p>Fill the pods with moist potting soil half-way. Add a fertilizer pellet to each pot and then add more soil to fill just below the lip. Make a shallow depression in the soil using a probe, the touch a clean toothpick to a gluestick and use this to transplant the seeds into the soil one by one.</p><p>Finally, cover the seeds with a thin layer of soil. Label the pots based on their hairiness line, and then place them in a designated growing area such as under a grow lamp or on a windowsill. Water them using a plastic dropper and repeat this often to ensure they don't dry out.</p><p>When the generation two plants are two weeks old, collect five plants from each line and label them A to E.Then count the trichomes in the same manner as for the first generation plants and record the trichome count results in the table, along with the class average for each line. To analyze the trichome leaf variations between the plant lines and generations, first create a frequency graph based on the generation one class data with the trichome count on the x axis and the number of plants on the y axis, and label the mean. Then create frequency graphs for both the selected lines of generation two and compare them to each other as well as to the graph for generation one.</p><p>Looking at the frequency graphs for each generation, you will notice a phenotypic shift toward a higher trichome count in the high hairiness group, while the low hairiness line would have shifted to a lower trichome count. You will also have noticed differences in the means between the generations and between the hairiness lines that mirror the shifts in distribution. What do you think the distributions would look like if the selection continued over more generations?</p>

artificial selection visualization plants

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LS.Bio.9.2

Use models to illustrate the conditions required for natural selection, including the overproduction of offspring, inherited variation, and the struggle to survive.

LS.Bio.9.3

Construct an explanation to explain how natural selection leads to adaptations within populations.

Extinction

The History of Life on Earth
Fossils of organisms that were different from anything alive today had been documented as early as the 17th century, but it ...

Diversity and Extinction during the Paleogene Epoch
ExpandFirst, familiarize yourself with the extinction reading supplement for the background on what ...

Diversity and Extinction during the Paleogene Epoch
ExpandBegin this procedure by reading the extinction reading supplement that has been printed out for ...

Construct explanations to illustrate how varying environmental conditions may result in: changes in the number of individuals of a species, the emergence of new species over time, or the extinction of other species.

LS.Bio.10.1

Synteny and Evolution

John H. Renwick first coined the term &#8220;synteny&#8221; in 1971, which refers to the genes present on the same chromosomes, even if they are not ...

Multi-species Conserved Sequences

Next-generation sequencing technologies have created large genomic databases of a variety of animals and plants. Ever since the human genome project was ...

Taxonomy

Taxonomy is the science of defining and naming groups of biological organisms based on shared characteristics. It uses a hierarchy of increasingly ...

Phylogeny

Phylogeny is concerned with the evolutionary diversification of organisms or groups of organisms. A group of organisms with a name is called a taxon ...

Use models (including dichotomous keys, scientific nomenclature, cladograms, phylogenetic trees) to identify organisms and exemplify relationships.

LS.Bio.10.2

Understand natural selection as a mechanism for biological evolution.

Artificial Selection

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Natural Selection and Adaptive Evolution

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