Name: patch use in optimal foraging
Uploaded: 2019-01-29T11:04:46.000Z
Duration: 3 min 37 s
Channel: JoVE

K12 Standards

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heredity-inheritance-and-variation-of-traits

Heredity: Inheritance and Variation of Traits

HS-LS4-2

Optimal Foraging

인생에서 개인이 필요로 하는 것들이 당장 손에 잡히지 않을 수도 있습니다. 따라서 유기체는 먹이를 찾아야 합니다. 채집은 단순히 음식 또는 더 일반적으로 자원을 찾는 과정으로 정의됩니다. 음식이 아마도 가장 먼저 떠오르는 예일 것이지만, 유기체는 피난처나 짝과 같은 다른 자원을 찾아 헤매야 하며 동물은 종종 필요한 것을 얻기 위해 많은 노력을 기울입니다. 그러나 먹이를 찾는 행위 자체에는 에너지가 필요합니다. 기본적으로 개인은 칼로리를 태우는 것과 섭취하는 것의 균형을 맞춰야 합니다. 간단히 말해서 채집에는 전략이 필요합니다. 생태학자들은 유기체가 채집하는 데 소비된 에너지, 즉 도토리 두 개의 가치와 6개의 새로운 도토리와 같이 얻을 수 있는 위치 에너지 사이의 최적의 균형을 충족하는 상황을 모델링하기 위해 최적의 채집 이론을 만들었습니다. 
채집의 한 가지 특징은 자원이 서식지 내에 항상 고르게 분포되어 있지 않다는 것입니다. 보다 일반적으로 자원은 채집자가 이동해야 하는 패치에 포함되어 있습니다. 그렇다면 채집자는 정확히 어떻게 이러한 자원 패치를 탐색해야 할까요? 1976년, 진화 생태학자 에릭 L. 차르노프(Eric L. Charnov)는 유기체가 먹이 찾기를 최적화하는 방법을 설명하기 위해 한계 가치 정리(Marginal Value Theorem, MVT)를 제시했다. MVT에는 최적의 먹이 찾기에 대한 5가지 주요 예측이 있습니다. 첫째, 수렵 채집자는 낮은 피식 밀도 패치보다 높은 피식 밀도를 가진 패치에서 더 많은 먹이를 잡아야 한다고 명시되어 있습니다. 둘째, 이 이론은 수렵 채집자가 높은 먹이 밀도 패치에서 자원을 찾는 데 더 많은 시간을 할애해야 한다고 예측합니다. 다음으로, 채집자는 패치가 더 멀리 퍼져 있는 희박한 환경보다 패치가 밀집되어 있는 밀집된 환경에서 더 높은 먹이 포획률을 가져야 합니다. 네 번째 예측은 수렵 채집자들이 희박한 환경보다 이러한 밀집된 환경에서 수렵을 찾는 데 더 많은 시간을 할애할 것이라는 것입니다. 마지막으로, 채집자는 포획률이 모든 패치의 평균 비율로 감소했을 때 패치를 남겨야 합니다. 그리고 여기에서 시간을 포기하거나 GUT라는 개념이 등장합니다. GUT를 계산하려면 개체가 패치를 떠난 시간에서 마지막 먹이 항목을 획득한 시간을 빼기만 하면 됩니다. 따라서 GUT는 채집자가 방문하는 모든 패치에 대해 동일해야 합니다. 
이 실험실에서는 여러 가지 인공 자원 패치에서 채집 시뮬레이션을 완료한 다음 계산을 수행하여 클래스가 채집자로서 어떻게 수행했는지, 한계 가치 정리의 규칙을 준수했는지 여부를 측정합니다.

최적의 채집

<h4>최적의 채집</h4>
유기체는 생존을 위해 환경에서 자원을 획득하고 사용해야 합니다. 먹이는 유기체가 찾아야 하는 주요 자원 중 하나이지만 개체도 서식지, 피난처 및 짝을 찾아야 합니다. 자원을 찾는 이러한 과정을 채집이라고 하며, 여기에는 일련의 비용과 이점이 포함됩니다. 좀 더 구체적으로 말하자면, 자원을 획득하는 것은 유기체에게 이득을 주지만, 자원을 찾고 포획하는 데는 시간과 에너지의 소비가 필요하다. 따라서 유기체는 가장 낮은 비용으로 최대의 이익을 제공함으로써 순 이득을 최적 수준으로 극대화하는 수렵 전략을 채택합니다. 생태학자들은 유기체가 채집 비용과 이익 사이의 최적 균형을 충족하는 상황을 모델링하기 위해 "최적 채집 이론"을 개발했습니다.
<h4>한계 가치 정리</h4>
리소스가 환경에서 균일하게 분산되지 않습니다. 예를 들어, 산림 생태계에서는 숲 전체에 고르게 분포되어 있기보다는 뭉쳐진 나무 종을 발견할 가능성이 훨씬 더 높습니다. 리소스 가용성의 이러한 이질성은 리소스의 "패치"를 만듭니다. 그러므로, 채집자들은 패치의 보상뿐만 아니라 패치 사이의 거리, 따라서 다른 패치로 이동하는 비용도 고려해야 합니다. 한계가치 정리(Marginal Value Theorem, MVT)는 최적의 수렵채집자가 서식지 1의 자원 패치를 어떻게 활용하고 이동하는지 설명합니다. MVT에 대한 5가지 주요 예측은 다음과 같습니다. 
<ol class="참조">
	<li>수렵 채집자는 낮은 피식 밀도의 패치보다 높은 피식 밀도의 패치에서 더 많은 먹이를 잡아야 합니다.</li>
	<li>수렵 채집자는 피식 밀도가 낮은 곳보다 피식 밀도가 높은 지역에서 수렵하는 데 더 많은 시간을 보내야 합니다.</li>
	<li>채집자는 멀리 퍼져 있는 수렵자보다 밀집된 지역에서 먹이 포획률이 더 높아야 합니다.</li>
	<li>채집자는 희박한 환경보다 패치가 밀집되어 있는 밀집된 환경에서 채집하는 데 더 많은 시간을 할애해야 합니다.</li>
	<li>채집자는 포획률이 모든 패치의 평균 비율로 감소했을 때 패치를 떠나야 합니다.</li>
</ol>
마지막 먹이가 포획된 시점과 채집자가 패치를 떠날 때 사이의 시간 간격은 GIVING-Up-Time 또는 GUT로 알려져 있습니다. MVT의 맥락에서 GUT는 각 개별 채집자에 대한 모든 패치에서 동일해야 합니다. 이것은 인공 솔방울에 숨겨진 밀웜을 찾는 대형 조류 사육장에서 검은머리박새를 대상으로 한 실험에서 테스트되었으며, 새들은 모든 유형의 패치에 대해 동일한 GUT를 가졌으며, 이는 전체 환경 2의 평균 포획률과 반비례했습니다. 
유기체가 먹이를 찾는 데 더 오래 소비할수록 더 많은 에너지를 소비하고 포식자와 요소에 더 오래 노출되므로 자원 획득을 위한 최적의 먹이 찾기 전략을 개발하는 것은 대부분의 유기체에게 필수적입니다. MVT의 원칙은 다양성, 보존, 심지어 인간 행동을 촉진하는 데 실제로 많이 적용됩니다.
<h4>변화하는 환경에서 최적의 채집</h4>
다양성과 보전의 관점에서 MVT는 생물의 에너지 수요를 적절하게 충족시킬 수 있는 패치가 있는 경우에만 종이 존재할 수 있다고 예측할 수 있으며, 따라서 생존을 위해 자원에 의존하는 유기체에게는 자원의 가용성과 자원 간의 거리가 중요합니다. 서식지 손실, 오염 및 기타 환경 변화는 유기체가 최적으로 먹이를 찾는 능력을 방해하여 적합성을 감소시킬 수 있습니다. 따라서 생태계의 서식지가 파괴되면 패치 또는 전체 커뮤니티가 제거됩니다. 이러한 제거는 생태계의 나머지 부분에 있는 주민들이 이용할 수 있는 자원을 제한한다. 자원이 있는 패치가 적을수록 경쟁이 더 치열해지고 특정 종을 제거할 수 있습니다. 이것은 서식지 손실로 인해 멸종 위기에 처한 종에게 특히 중요하며, 서식지의 대부분이 파괴되면 먹이 찾기에 필요한 것을 충족시킬 수 없게 될 것입니다. 
인간은 채집의 필요성을 제한하기 위해 정교한 식량 저장고를 개발했지만, 저렴한 주택, 보수가 좋은 직업 또는 적절한 데이트 장소를 찾는 것과 같이 채집이 필요한 다른 많은 경우가 있습니다. 최근 연구에서는 일반의의 정보 탐색 능력을 사용하여 MVT의 예측을 테스트했습니다. 그들은 일반 개업의가 환자를 진단할 때 정보를 최적으로 수집한다는 것을 발견했습니다. 그들은 여러 정보 출처 사이를 빠르게 이동했으며, 인터넷과 같은 고밀도 소스와 동료를 포함하여 쉽게 얻을 수 있는 소스를 모두 자주 활용했습니다 3. 이와 유사하게, 최적 채집 이론(Optimal Foraging Theory)은 소비자가 제품을 구매하거나 물건을 구매할 때 제품과 정보를 "채집"하는 방법의 경제학에도 적용된다 4. 이러한 연구는 인간이 다양한 맥락에서 최적 채집 이론의 예측을 어떻게 고수하는지 보여줍니다.
<h4>참조</h4>
<ol>
	<li>Charnov, E. L. ptimal 채집: 한계 가치 정리. 이론적 인구 생물학. 1976년, Vol. 9, (129-36).</li>
	<li>존 크렙스, 존 라이언, 에릭 샤르노프. 기대 또는 최적의 먹이 찾기에 의한 사냥 : 박새의 패치 사용에 대한 연구. 동물 행동. 1974년, Vol. 22, (953-64).</li>
	<li>마이 드와이리, 앤서니 C 도웰, 장 클로드 스탈. 일반 개업의의 정보 검색 행동에 대한 채집 이론의 적용. BMC 가족 실습. 2011년, Vol. 12, 90.</li>
	<li>웰스, V.K. 채집: 소비자 행동의 생태학적 모델? 마케팅 이론. 2012년, Vol. 2, 12 (117-136).</li>
</ol>

최적의 채집
유기체는 생존을 위해 환경에서 자원을 획득하고 사용해야 합니다. 음식은 유기체가 해야 하는 주요 자원 중 하나이지만 ...

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patch use in optimal foraging

Patch use in optimal foraging explains how organisms balance food gain against the time and energy needed to search for it. Foraging is not limited to food. Animals also search for habitats, shelter, and mates. Each choice has costs and benefits. A resource provides a benefit, but finding and capturing it takes effort. Optimal Foraging Theory models how organisms reach the best balance between those costs and gains.

A key idea in this theory is that resources are often clumped into patches rather than spread evenly through an environment. Forest trees, for example, are more likely to occur in groups than as single, evenly spaced trees. Because of this patchiness, foragers must think about both the value of a patch and the distance to the next one. Moving between patches also has a cost. The Marginal Value Theorem helps explain when an organism should keep feeding in a patch and when it should move on.

The Marginal Value Theorem predicts that foragers should capture more prey in dense patches than in sparse ones. They should also spend more time in patches with more prey, and they should have a higher prey capture rate there. In dense environments, where patches are closer together, foragers should spend more time foraging than in sparse environments. A forager should leave a patch when the capture rate falls to the average rate for the whole environment. The time between the last prey capture and leaving the patch is called the Giving-Up-Time, or GUT.

The GUT should be the same across patches for a single forager. This prediction was tested with black-capped chickadees in a large aviary. The birds searched for mealworms hidden in artificial pine cones. They showed the same GUT in all patch types, and that GUT was inversely related to the average capture rate in the environment. The result supported the Marginal Value Theorem.

Optimal foraging matters because searching takes time, uses energy, and can expose organisms to predators and the elements. It also helps explain real-world ecology and conservation. Habitat loss, pollution, and other environmental changes can disrupt foraging and lower fitness. If habitats are destroyed, patches and even whole communities may disappear. That reduces the resources available to the rest of the ecosystem and can increase competition. Species at risk of extinction may be especially affected if most of their habitat is lost.

The same ideas also apply to human behavior. Humans reduce foraging needs through food storage, but they still forage in other ways. People may search for affordable housing, a well-paying job, or a suitable date. A study of general practitioners found that they foraged for information while diagnosing patients. They moved quickly between sources and used both high-density sources, such as the internet, and easier sources, including colleagues. Optimal Foraging Theory also helps explain how consumers search for products and information when making purchases.

Patch Use in Optimal Foraging

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DNA as a Genetic Template

Structure of a Gene

A gene is the fundamental unit of heredity. Every individual has two copies of each gene, one inherited from each parent. Although most people contain the ...

DNA Packaging

Organization of Genes

Chromosome Structure

A functional eukaryotic chromosome must contain three elements: a centromere, telomeres, and numerous origins of replication.
The centromere is a DNA ...

The Nucleosome

DNA in a human cell is almost 2m long and it is packed inside a tiny nucleus that is only a few microns in diameter. The level of compaction of DNA inside ...

Chromatin Packaging

Each human somatic cell contains 6 billion base-pairs of DNA. Each base-pair is 0.34 nm long, which means that each diploid cell contains a staggering 2 ...

Karyotyping

Position-effect Variegation

In 1928, a German botanist Emil Heitz observed the moss nuclei with a DNA binding dye. He observed that while some chromatin regions decondense and spread ...

Histone Modification

The histone proteins have a flexible N-terminal tail extending out from the nucleosome. These histone tails are often subjected to post-translational ...

Spreading of Chromatin Modifications

The histone&#160;proteins in the nucleosomes are post-translationally modified (PTM) to increase or decrease access to DNA. The commonly observed PTMs are ...

Lampbrush Chromosomes

In 1882, Flemming observed lampbrush chromosomes (LBC) in salamander eggs. Later in 1892, R&#252;ckert observed LBCs in shark egg cells and coined the ...

Polytene Chromosomes

Polytene chromosomes are giant interphase chromosomes with several DNA strands placed side by side. They were discovered in the year 1881 by Balbiani in ...

Histone Variants at the Centromere

Histone variants are the histone proteins with structural and sequence variations. These variants may be regarded as &#8220;mutant&#8221; forms that ...

Inheritance of Chromatin Structures

Epigenetics is the study of inherited changes in a cell&#39;s phenotype without changing the DNA sequences. It provides a form of memory for the ...

Euchromatin

The extent of chromatin compaction can be studied by staining chromatin using specific DNA binding dyes. Under the microscope, the dense-compacted regions ...

Heterochromatin

chromatin-position-affects-gene-expression

Chromatin Position Affects Gene Expression

Chromatin is the massive complex of DNA and proteins packaged inside the nucleus. The complexity of chromatin folding and how it is packaged inside the ...

Genetics of Organisms

Mendelian Genetics
Evolution is caused by changes in the genetic composition of populations. In the field of population genetics, scientists model this ...

REF and WEF Fly Genetics
ExpandTo prepare for the experiment, be sure to obtain cultures of Drosophila melanogaster at least two weeks ahead of the ...

REF and WEF Fly Genetics
ExpandNOTE: At your station, you should have four vials of flies. They will be labeled as male or female. They will also be ...

Genetic Lingo

Overview

An organism is diploid if it inherits two variants, or alleles, of each gene, one from each parent. These two alleles constitute the genotype ...

Punnett Squares

Overview

A Punnett square displays the possible genotypes offspring can inherit from two parental genotypes. If a trait&#x2019;s inheritance pattern ...

Monohybrid Crosses

Overview

In the 1850s and 1860s, Gregor Mendel investigated inheritance by performing monohybrid crosses in pea plants. He crossed two plants that were ...

Dihybrid Crosses

Overview

To determine whether traits are inherited together or separately, Gregor Mendel crossed pea plants that differed in two traits. These parental ...

Trihybrid Crosses

Trihybrid Crosses
Some of Mendel&#8217;s crosses examined three pairs of contrasting characteristics. Such a cross is called a trihybrid cross. A ...

Law of Segregation

When crossing pea plants, Mendel noticed that one of the parental traits would sometimes disappear in the first generation of offspring, called the F1 ...

Law of Independent Assortment

While Mendel&#x2019;s Law of Segregation states that the two alleles for one gene are separated into different gametes, a different question of how ...

Test Cross

Alleles are different forms of the same gene. Humans and other diploid organisms inherit two alleles of every gene, one from each parent.

An allele is ...

Chi-square Analysis

The chi-square test is a statistical hypothesis test. It is used to check whether there is a significant difference between an expected value and an ...

Pedigree Analysis

Overview

A pedigree is a diagram displaying a family&#x2019;s history of a trait. Analyzing pedigrees can reveal (1) whether a trait is dominant or ...

Nature and Nurture

Many human characteristics, like height, are shaped by both nature&mdash;in other words, by our genes&mdash;and by nurture, or our environment. For ...

Probability Laws

Overview

The probability of inheriting a trait can be calculated using the sum and product rules. The sum rule is used to calculate the probability of ...

background-and-environment-affect-phenotype

Background and Environment Affect Phenotype

Although the genetic makeup of an organism plays a major role in determining the phenotype, there are also several environmental factors, such as ...

Multiple Allele Traits

The Concept of Multiple Allelism

Multiple allelism describes genes that exist in three or more allelic forms. Although diploid organisms, like humans, ...

X and Y Chromosomes

Among mammals, the gender of an organism is determined by the sex chromosomes. Humans have two sex chromosomes, X and Y. Every human diploid cell has 22 ...

Chromosomal Theory of Inheritance

In 1866, Gregor Mendel published the results of his pea plant breeding experiments, providing evidence for predictable patterns in the inheritance of ...

The Y Chromosome Determines Maleness

The Y chromosome is a sex chromosome&#160;found in several vertebrates and mammals, including humans. In addition to 22 pairs of autosomes, the human ...

Non-nuclear Inheritance

Most DNA resides in the nucleus of a cell. However, some organelles in the cell cytoplasm⁠&mdash;such as chloroplasts and mitochondria⁠&mdash;also ...

The Ratio of X Chromosome to Autosomes

In most organisms, sex is determined by the ratio of X and Y chromosomes. However, in some organisms, such as Drosophila and C.elegans, sex is determined ...

Incomplete Dominance

Gregor Mendel&#39;s work (1822 - 1884) was primarily focused on pea plants. Through his initial experiments, he determined that every gene in a diploid ...

X-linked Traits

In most mammalian species, females have two X sex chromosomes and males have an X and Y. As a result, mutations on the X chromosome in females may be ...

Lethal Alleles

Agouti: A Lethal Allele
Lucien Cu&#233;not discovered lethal alleles in 1905 while studying the inheritance of coat color in mice. The agouti gene is ...

Sex-linked Disorders

Like autosomes, sex chromosomes contain a variety of genes necessary for normal body function. When a mutation in one of these genes results in biological ...

Epistasis

In addition to multiple alleles at the same locus influencing traits, numerous genes or alleles at different locations may interact and influence ...

X-Inactivation

The human X chromosome contains over ten times the number of genes as in the Y chromosome. Since males have only one X chromosome, and females have two, ...

Polygenic Traits

When more than one gene is responsible for a given phenotype, the trait is considered polygenic. Human height is a polygenic trait. Studies have uncovered ...

Dosage Compensation

In animals, gender is determined by the number and type of sex chromosome. For example, human females have two X chromosomes, and males have one X and one ...

Pleiotropy

Pleiotropy is the phenomenon in which a single gene impacts multiple, seemingly unrelated phenotypic traits. For example, defects in the SOX10 gene cause ...

Ask questions to clarify relationships about the role of DNA and chromosomes in coding the instructions for characteristic traits passed from parents to offspring. [Assessment Boundary: Assessment does not include the phases of meiosis or the biochemical mechanism of specific steps in the process.]

HS-LS3-1

genome-size-and-the-evolution-of-new-genes

Genome Size and the Evolution of New Genes

Gene Families

Gene Evolution - Fast or Slow?

types-of-genetic-transfer-between-organisms

Types of Genetic Transfer Between Organisms

What is Meiosis?

Meiosis I

Meiosis is the division of a diploid cell into haploid cells forming sperm and eggs in animals through differentiation. Meiosis I is the first stage of ...

Meiosis II

Meiosis II entails cell division and segregation of the sister chromatids, resulting in the production of four unique haploid gametes. The steps for ...

Meiosis vs. Mitosis

Cell division is necessary for growth and reproduction in organisms. Mitosis aids cell growth and development by dividing somatic cells. In contrast, ...

Crossing over

Nondisjunction

Replication in Eukaryotes

Overview

In eukaryotic cells, DNA replication is highly conserved and tightly regulated. Multiple linear chromosomes must be duplicated with high ...

Proofreading

Synthesis of new DNA molecules starts when DNA polymerase links nucleotides together in a sequence that is complementary to the template DNA strand. DNA ...

Mismatch Repair

Overview

Organisms are capable of detecting and fixing nucleotide mismatches that occur during DNA replication. This sophisticated process requires ...

Nucleotide Excision Repair

Overview

Exposure to mutagens can damage DNA and result in bulky lesions that distort the double-helix structure or impede proper transcription. Damaged ...

Cancer Prevention

Several factors can increase the risk of cancer in an individual. About 50% of cancer cases can be prevented by adopting a healthy lifestyle, regular ...

cancers-originate-from-somatic-mutations-in-a-single-cell

Cancers Originate from Somatic Mutations in a Single Cell

Cancer arises from mutations in the critical genes that allow healthy cells to escape cell cycle regulation and acquire the ability to proliferate ...

DNA Distortion and Damage
Cells are regularly exposed to mutagens&#8212;factors in the environment that can damage DNA and generate mutations. UV ...

comparing-copy-number-variations-and-snps

Comparing Copy Number Variations and SNPs

Sequencing of the human genome has opened up several best-kept secrets of the genome. Scientists have identified thousands of genome variations that exist ...

Gene Conversion

Other than maintaining genome stability via DNA repair, homologous recombination plays an important role in diversifying the genome. In fact, the ...

Mutations

Overview

Mutations are changes in the sequence of DNA. These changes can occur spontaneously or they can be induced by exposure to environmental factors. ...

Mutation, Gene Flow, and Genetic Drift

In a population that is not at Hardy-Weinberg equilibrium, the frequency of alleles changes over time. Therefore, any deviations from the five conditions ...

Make and defend a claim based on evidence that inheritable genetic variations may result from (1) new genetic combinations through meiosis, (2) viable errors occurring during replication, and or (3) mutations caused by environmental factors. [Clarification Statement: Emphasis is on using data to support arguments for the way variation occurs.] [Assessment Boundary: Assessment does not include the phases of meiosis or the biochemical mechanism of specific steps in the process.]

HS-LS3-2

Patch Use in Optimal Foraging

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