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

K12 Standards

Next Generation Science Standards

High School

Life Science

heredity-inheritance-and-variation-of-traits

Heredity: Inheritance and Variation of Traits

HS-LS4-2

Optimal Foraging

人生では、個人が必要とするものがすぐには手に入れられないことがよくあります。ですから、生物は採餌する必要があります。採餌は、単に食料やより一般的には資源を探すプロセスとして定義されています。食べ物がおそらく最初に頭に浮かぶ例ですが、生物は避難所や仲間などの他の資源を探す必要があり、動物は必要なものを手に入れるために多大な努力を払うことがよくあります。しかし、採集するという行為自体にエネルギーが必要です。基本的に、個人はカロリーの燃焼とカロリーの獲得のバランスをとる必要があります。簡単に言えば、採集には戦略が必要です。生態学者は、生物が採餌に消費されたエネルギー、つまり2つのドングリの価値と、6つの新しいドングリのように獲得できる位置エネルギーとの間の最適なバランスを満たす状況をモデル化するために、最適な採餌理論を作成しました。
採餌の特徴の1つは、資源が生息地内で常に均等に分散しているとは限らないことです。より一般的には、資源は採集者が移動しなければならないパッチに含まれています。では、採集者はこれらの資源のパッチをどのように正確にナビゲートすべきでしょうか?1976年、進化生態学者のエリック・L・チャーノフは、生物が採餌を最適化する方法を説明するために、限界価値定理またはMVTを考案しました。MVTには、最適な採餌のための5つの主要な予測があります。まず、採餌者は、獲物密度の低いパッチよりも、獲物密度の高いパッチでより多くの獲物を捕獲する必要があると述べています。第二に、この理論では、採集者は獲物密度の高い地域で資源を探すためにより多くの時間を費やすべきであると予測しています。次に、採餌者は、パッチが密集している密集した環境で、パッチがさらに分散しているまばらな環境よりも獲物の捕獲率が高くなるはずです。4番目の予測では、採集者は、まばらな環境よりもこれらの密集した環境で採餌に多くの時間を費やすと述べています。最後に、捕獲者がパッチを離れるのは、捕獲率がすべてのパッチの平均率まで低下した場合です。そこで登場するのが、ギブアップ・タイム(GUT)と呼ばれる概念です。GUTを計算するには、個体がパッチを離れた時間から最終的な獲物アイテムが取得された時間を差し引くだけです。したがって、GUTは、採餌者が訪れるすべてのパッチで同じである必要があります。
この研究室では、いくつかの異なる人工資源パッチで採餌シミュレーションを行い、次に計算を実行して、採餌者としてのクラスのパフォーマンスと、限界値定理のルールを遵守しているかどうかを評価します

最適な採餌

<h4>最適な採餌</h4>
生物は生き残るために、環境内の資源を獲得し、使用する必要があります。食物は生物が探さなければならない主要な資源の1つですが、個体は生息地、避難所、仲間を探す必要もあります。資源を探すこのプロセスは採餌として知られており、これには一連のコストとメリットが伴います。より具体的には、資源を獲得することは生物に利益をもたらしますが、資源を探して捕獲するには時間とエネルギーの消費が必要です。したがって、生物は、最小のコストで最大の利益を提供することにより、純利益を最適なレベルに最大化する採餌戦略を採用しています。 生態学者は、生物が採餌のコストと利益の最適なバランスを満たす状況をモデル化するために、「最適採餌理論」を開発しました。
<h4>限界価値定理</h4>
リソースは環境内で均一に分散されていません。たとえば、森林生態系では、森林全体に均等に分布しているのではなく、樹種が密集している可能性がはるかに高くなります。このリソースの可用性の不均一性は、リソースの「パッチ」を作成します。したがって、採集者は、パッチの見返りとパッチ間の距離、したがって別のパッチに移動するコストの両方を考慮する必要があります。限界価値定理(MVT)は、最適な採餌者が生息地の資源をどのように利用し、移動するかを説明しています1。MVTには、主に5つの予測があります。 
<ol class="references">
	<li>採餌者は、獲物密度の低いパッチよりも、獲物密度の高いパッチでより多くの獲物を捕獲する必要があります。</li>
	<li>採餌者は、獲物密度の低いパッチよりも、獲物密度の高いパッチで採餌により多くの時間を費やす必要があります。</li>
	<li>採餌者は、遠くに広がっているものよりも密集したパッチで獲物を捕獲する率が高いはずです。</li>
	<li>採集者は、まばらな環境よりも、パッチが密集している密集した環境で採餌に多くの時間を費やす必要があります。</li>
	<li>採集者は、捕獲率がすべてのパッチの平均率に低下したときにパッチを離れる必要があります。</li>
</ol>
最後の獲物が捕獲されてから、採餌者がパッチを離れるまでの時間間隔は、ギビングアップタイム(GUT)として知られています。MVT のコンテキストでは、GUT は個々の採集者のすべてのパッチで同じである必要があります。これは、人工の松ぼっくりに隠れたミールワームを探す大きな鳥小屋の黒い帽子をかぶったヒヨドリを使った実験でテストされました。そこでは、鳥はすべてのタイプのパッチに対して同じGUTを持っていました。これは、環境全体の平均捕獲率に反比例していました2。
生物が採餌に費やす時間が長ければ長いほど、より多くのエネルギーを消費し、捕食者や要素に身をさらす時間が長くなるため、資源獲得のための最適な採餌戦略を開発することは、ほとんどの生物にとって不可欠です。MVTの原則は、多様性、保全、さらには人間の行動を促進するための多くの現実的な応用があります。
<h4>変化する環境での最適な採餌</h4>
多様性と保全の観点から、MVTは、生物のエネルギー需要を適切に満たすパッチがある場合にのみ種が存在すると予測し、したがって、生存のためにそれらに依存する生物にとって、資源の利用可能性と資源間の距離は重要です。生息地の喪失、汚染、およびその他の環境の変化は、生物が最適に採餌する能力を妨げ、したがってその適応度を低下させる可能性があります。したがって、生態系の生息地が破壊されると、パッチまたはコミュニティ全体が削除されます。この除去により、生態系の残りの部分の住民が利用できる資源が制限されます。資源のあるパッチが少ないほど、競争が激しくなり、特定の種が排除される可能性があります。これは、生息地の喪失により絶滅の危機に瀕している種にとって特に重要であり、生息地のほとんどが破壊された場合、採餌のニーズを満たすことができなくなります。
人間は、採餌のニーズを制限するために高度な食料貯蔵を開発しましたが、手頃な価格の住宅、高給の仕事、適切な日付の検索など、採餌が必要な他の多くの例があります。最近の研究では、一般開業医の情報探索能力を使用してMVTの予測をテストしました。彼らは、一般開業医が患者を診断する際に情報を最適に探していることを発見しました。彼らは複数の情報源間をすばやく移動し、インターネットなどの高密度の情報源と、同僚を含む簡単に入手できる情報源の両方を利用しました3。同様に、最適採餌理論は、消費者が買い物をする方法、または購入時に製品や情報を「探す」方法の経済学にも適用されます4。これらの研究は、人間がさまざまな状況で最適採餌理論の予測にどのように固執するかを示しています。
<h4>参照</h4>
<ol>
	<li>Charnov、ELのptimal採餌:限界価値定理。理論集団生物学。 1976年、第9巻、(129-36)。</li>
	<li>ジョン・クレブス、ジョン・ライアン、エリック・チャーノフ。期待値または最適な採餌による狩猟:ヒヨドリによるパッチ使用の研究。動物の行動。 1974年、第22巻、(953-64)。</li>
	<li>マイ・ドウェイリー、アンソニー・C・ダウエル、ジャン・クロード・スタール。一般開業医の情報検索行動への採餌理論の応用。BMCファミリープラクティス。 2011年、第12巻、90。</li>
	<li>ウェルズ、VK採集:消費者行動のエコロジーモデル?マーケティング理論。 2012年、第2巻、12(117-136)。</li>
</ol>

最適な採餌
生物は生き残るために、環境内の資源を獲得し、使用する必要があります。食物は主要な資源の1つですが、生物は...

Education

JoVE Lab Manual

Biology

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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

animal behavior

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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...

sexual selection and mate choice

Mate Competition and Fitness Traits

Mate competition and fitness traits shape how organisms choose partners and pass genes to the next generation. Evolutionary fitness depends on surviving and producing offspring, and sexual selection is a major part of that process. It creates pressure on traits used in courtship and mating, such as bright colors, ornamentation, and other features that help attract a mate. These traits can also create sexual dimorphism, which means males and females of the same species look different. Sexual...

eusociality and division of labor

Honeybee Altruism and Inclusive Fitness

Eusociality is a highly organized form of animal social life. It includes division of labor, where different individuals take on different roles in the group. In these systems, some animals help others even when it comes at a cost to their own survival or reproduction. That self-sacrificing behavior is called altruism. Early evolutionary biologists used to explain fitness only at the level of the individual. Observations of eusocial species, such as honeybees, challenged that idea. W. D.

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Learn how optimal foraging theory explains patch use, Giving-Up-Time, and the Marginal Value Theorem using chickadees, conservation, and human examples.

Patch Use in Optimal Foraging | JoVE K12

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New York State Science Learning Standards

Natural Selection and Evolution

HS-LS4-1.

最適な採餌 を教える準備を、この 3 分間の教員向けガイドで行いましょう。JoVE Lab Manual の Biology ラボの主要な準備手順を解説します。

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DNA as a Genetic Template

Structure of a Gene

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DNA Packaging

Organization of Genes

Chromosome Structure

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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

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Karyotyping

Position-effect Variegation

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Histone Modification

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Spreading of Chromatin Modifications

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Lampbrush Chromosomes

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Polytene Chromosomes

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Inheritance of Chromatin Structures

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Euchromatin

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Heterochromatin

chromatin-position-affects-gene-expression

Chromatin Position Affects Gene Expression

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Genetics of Organisms

Mendelian Genetics
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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
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Law of Segregation

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Law of Independent Assortment

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Test Cross

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Chi-square Analysis

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Pedigree Analysis

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Nature and Nurture

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Probability Laws

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Background and Environment Affect Phenotype

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Multiple Allele Traits

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X and Y Chromosomes

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Chromosomal Theory of Inheritance

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The Y Chromosome Determines Maleness

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Non-nuclear Inheritance

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Incomplete Dominance

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X-linked Traits

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Lethal Alleles

Agouti: A Lethal Allele
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Sex-linked Disorders

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Epistasis

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X-Inactivation

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Polygenic Traits

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Dosage Compensation

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Pleiotropy

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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 ...

Viral Mutations

A mutation is a change in the sequence of bases of DNA or RNA in a genome. Some mutations occur during replication of the genome due to errors made by the ...

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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