HS-LS4-2 - Revision history

Conrad: PLD table: tag each question chip with its exam discipline for color coding

2026-10-18T13:46:57Z

PLD table: tag each question chip with its exam discipline for color coding

Conrad: PLD table: abbreviate question labels to match the questions-by-performance-level pages (e.g. "Aug 2026 · Q14")

2026-10-18T13:33:54Z

PLD table: abbreviate question labels to match the questions-by-performance-level pages (e.g. "Aug 2026 · Q14")

Conrad: PLD table: list all released questions at each level, matching the questions-by-performance-level pages

2026-10-18T12:05:44Z

PLD table: list all released questions at each level, matching the questions-by-performance-level pages

Conrad: PLDs: add example released question per level (editor judgment)

2026-10-16T06:38:10Z

PLDs: add example released question per level (editor judgment)

Conrad: Section order: Vocabulary now comes before Performance Level Descriptions

2026-10-13T17:27:18Z

Section order: Vocabulary now comes before Performance Level Descriptions

Conrad: SEO: topic in title, description, exam names in link text, standard template now sets the title

2026-10-13T17:00:54Z

SEO: topic in title, description, exam names in link text, standard template now sets the title

Conrad: Add Vocabulary section (Biology)

2026-09-27T21:47:42Z

Add Vocabulary section (Biology)

Conradrichman: Reorder sections: Assessment, then Performance Level Descriptions, then Resources

2026-09-21T02:35:55Z

Reorder sections: Assessment, then Performance Level Descriptions, then Resources

Conradrichman: Assessment section: table of all tagged exam and sample-cluster questions, grouped by subject and exam (most recent first)

2026-09-21T02:22:36Z

Assessment section: table of all tagged exam and sample-cluster questions, grouped by subject and exam (most recent first)

Conradrichman: Removed "* (NYSED) Individuals of a species with certain traits are more likely than others to survive and reproduce in a given environment. ". Doesn't seem to be in the NYSED pdf. This discrepancy was reported through the Google Form.

2025-08-22T01:12:18Z

Removed "* (NYSED) Individuals of a species with certain traits are more likely than others to survive and reproduce in a given environment. ". Doesn't seem to be in the NYSED pdf. This discrepancy was reported through the Google Form.

@@ Line 193: / Line 193: @@
 | Level4 = Construct an explanation based on evidence that the process of evolution primarily results from four factors: (1) the potential of species to increase in number, (2) the heritable genetic variation of individuals in a species due to mutation and sexual reproduction, (3) competition for limited resources, and (4) the proliferation of those organisms that are better able to survive and reproduce in the environment.
 | Level3 = Construct an explanation based on evidence that the process of evolution can involve: (1) the potential of species to increase in number, and/or (2) the heritable genetic variation of individuals in a species due to mutation and sexual reproduction, and/or (3) competition for limited resources, and/or (4) the proliferation of those organisms that are better able to survive and reproduce in the environment.
-| Example3 = [[Questions:A Seasonal Strategy for Survival#q5|June 2026 · Q5]] [[Questions:Australian Adaptations#q3|June 2026 · Q44]] [[Questions:Buzzy Bees#q2|June 2026 · Q29]] [[Questions:Strategies for Survival in Different Animal Species#q2|Aug 2025 · Q6]] [[Questions:Strategies for Survival in Different Animal Species#q5|Aug 2025 · Q9]] [[Questions:Limb Evolution#q3|June 2025 · Q30]]
+| Example3 = <span class="pld-chip pld-chip-bio">[[Questions:A Seasonal Strategy for Survival#q5|June 2026 · Q5]]</span> <span class="pld-chip pld-chip-bio">[[Questions:Australian Adaptations#q3|June 2026 · Q44]]</span> <span class="pld-chip pld-chip-bio">[[Questions:Buzzy Bees#q2|June 2026 · Q29]]</span> <span class="pld-chip pld-chip-bio">[[Questions:Strategies for Survival in Different Animal Species#q2|Aug 2025 · Q6]]</span> <span class="pld-chip pld-chip-bio">[[Questions:Strategies for Survival in Different Animal Species#q5|Aug 2025 · Q9]]</span> <span class="pld-chip pld-chip-bio">[[Questions:Limb Evolution#q3|June 2025 · Q30]]</span>
 | Level2 = Identify the explanation based on evidence that evolution is the result of genetic and/or environmental factor(s) or justify why the given explanation is correct or incorrect.
-| Example2 = [[Questions:Star of the Tide Pool#q1|Aug 2026 · Q1]] [[Questions:Honeybee Behavior and Threats#q4|Jan 2026 · Q31]] [[Questions:Zebra Coat Patterns#q3|Jan 2026 · Q43]] [[Questions:Evolutionary Relationships Biology#q2|Aug 2025 · Q34]] [[Questions:Keratin – A Very Versatile Protein#q5|Aug 2025 · Q28]] [[Questions:Dinosaurs Evolution Sample Cluster#q1|June 2025 · Q1]] [[Questions:Drinking Water Is Just The Beginning!#q2|June 2025 · Q7]] [[Questions:Heads or Tails?#q2|June 2025 · Q12]]
+| Example2 = <span class="pld-chip pld-chip-bio">[[Questions:Star of the Tide Pool#q1|Aug 2026 · Q1]]</span> <span class="pld-chip pld-chip-bio">[[Questions:Honeybee Behavior and Threats#q4|Jan 2026 · Q31]]</span> <span class="pld-chip pld-chip-bio">[[Questions:Zebra Coat Patterns#q3|Jan 2026 · Q43]]</span> <span class="pld-chip pld-chip-bio">[[Questions:Evolutionary Relationships Biology#q2|Aug 2025 · Q34]]</span> <span class="pld-chip pld-chip-bio">[[Questions:Keratin – A Very Versatile Protein#q5|Aug 2025 · Q28]]</span> <span class="pld-chip pld-chip-bio">[[Questions:Dinosaurs Evolution Sample Cluster#q1|June 2025 · Q1]]</span> <span class="pld-chip pld-chip-bio">[[Questions:Drinking Water Is Just The Beginning!#q2|June 2025 · Q7]]</span> <span class="pld-chip pld-chip-bio">[[Questions:Heads or Tails?#q2|June 2025 · Q12]]</span>
 | Level1 = Identify the evidence, from those provided, that supports the explanation that evolution is the result of a genetic and/or an environmental factor.
-| Example1 = [[Questions:Green and Black Frogs#q2|June 2026 · Q11]] [[Questions:Baboon Evolution#q2|Jan 2026 · Q34]] [[Questions:Limb Evolution#q5|June 2025 · Q32]]
+| Example1 = <span class="pld-chip pld-chip-bio">[[Questions:Green and Black Frogs#q2|June 2026 · Q11]]</span> <span class="pld-chip pld-chip-bio">[[Questions:Baboon Evolution#q2|Jan 2026 · Q34]]</span> <span class="pld-chip pld-chip-bio">[[Questions:Limb Evolution#q5|June 2025 · Q32]]</span>
 }}

@@ Line 193: / Line 193: @@
 | Level4 = Construct an explanation based on evidence that the process of evolution primarily results from four factors: (1) the potential of species to increase in number, (2) the heritable genetic variation of individuals in a species due to mutation and sexual reproduction, (3) competition for limited resources, and (4) the proliferation of those organisms that are better able to survive and reproduce in the environment.
 | Level3 = Construct an explanation based on evidence that the process of evolution can involve: (1) the potential of species to increase in number, and/or (2) the heritable genetic variation of individuals in a species due to mutation and sexual reproduction, and/or (3) competition for limited resources, and/or (4) the proliferation of those organisms that are better able to survive and reproduce in the environment.
-| Example3 = [[Questions:A Seasonal Strategy for Survival#q5|June 2026 Question 5]], [[Questions:Australian Adaptations#q3|June 2026 Question 44]], [[Questions:Buzzy Bees#q2|June 2026 Question 29]], [[Questions:Strategies for Survival in Different Animal Species#q2|August 2025 Question 6]], [[Questions:Strategies for Survival in Different Animal Species#q5|August 2025 Question 9]], [[Questions:Limb Evolution#q3|June 2025 Question 30]]
+| Example3 = [[Questions:A Seasonal Strategy for Survival#q5|June 2026 · Q5]] [[Questions:Australian Adaptations#q3|June 2026 · Q44]] [[Questions:Buzzy Bees#q2|June 2026 · Q29]] [[Questions:Strategies for Survival in Different Animal Species#q2|Aug 2025 · Q6]] [[Questions:Strategies for Survival in Different Animal Species#q5|Aug 2025 · Q9]] [[Questions:Limb Evolution#q3|June 2025 · Q30]]
 | Level2 = Identify the explanation based on evidence that evolution is the result of genetic and/or environmental factor(s) or justify why the given explanation is correct or incorrect.
-| Example2 = [[Questions:Star of the Tide Pool#q1|August 2026 Question 1]], [[Questions:Honeybee Behavior and Threats#q4|January 2026 Question 31]], [[Questions:Zebra Coat Patterns#q3|January 2026 Question 43]], [[Questions:Evolutionary Relationships Biology#q2|August 2025 Question 34]], [[Questions:Keratin – A Very Versatile Protein#q5|August 2025 Question 28]], [[Questions:Dinosaurs Evolution Sample Cluster#q1|June 2025 Question 1]], [[Questions:Drinking Water Is Just The Beginning!#q2|June 2025 Question 7]], [[Questions:Heads or Tails?#q2|June 2025 Question 12]]
+| Example2 = [[Questions:Star of the Tide Pool#q1|Aug 2026 · Q1]] [[Questions:Honeybee Behavior and Threats#q4|Jan 2026 · Q31]] [[Questions:Zebra Coat Patterns#q3|Jan 2026 · Q43]] [[Questions:Evolutionary Relationships Biology#q2|Aug 2025 · Q34]] [[Questions:Keratin – A Very Versatile Protein#q5|Aug 2025 · Q28]] [[Questions:Dinosaurs Evolution Sample Cluster#q1|June 2025 · Q1]] [[Questions:Drinking Water Is Just The Beginning!#q2|June 2025 · Q7]] [[Questions:Heads or Tails?#q2|June 2025 · Q12]]
 | Level1 = Identify the evidence, from those provided, that supports the explanation that evolution is the result of a genetic and/or an environmental factor.
-| Example1 = [[Questions:Green and Black Frogs#q2|June 2026 Question 11]], [[Questions:Baboon Evolution#q2|January 2026 Question 34]], [[Questions:Limb Evolution#q5|June 2025 Question 32]]
+| Example1 = [[Questions:Green and Black Frogs#q2|June 2026 · Q11]] [[Questions:Baboon Evolution#q2|Jan 2026 · Q34]] [[Questions:Limb Evolution#q5|June 2025 · Q32]]
 }}

@@ Line 193: / Line 193: @@
 | Level4 = Construct an explanation based on evidence that the process of evolution primarily results from four factors: (1) the potential of species to increase in number, (2) the heritable genetic variation of individuals in a species due to mutation and sexual reproduction, (3) competition for limited resources, and (4) the proliferation of those organisms that are better able to survive and reproduce in the environment.
 | Level3 = Construct an explanation based on evidence that the process of evolution can involve: (1) the potential of species to increase in number, and/or (2) the heritable genetic variation of individuals in a species due to mutation and sexual reproduction, and/or (3) competition for limited resources, and/or (4) the proliferation of those organisms that are better able to survive and reproduce in the environment.
-| Example3 = [[Questions:A Seasonal Strategy for Survival#q5|June 2026 Question 5]]
+| Example3 = [[Questions:A Seasonal Strategy for Survival#q5|June 2026 Question 5]], [[Questions:Australian Adaptations#q3|June 2026 Question 44]], [[Questions:Buzzy Bees#q2|June 2026 Question 29]], [[Questions:Strategies for Survival in Different Animal Species#q2|August 2025 Question 6]], [[Questions:Strategies for Survival in Different Animal Species#q5|August 2025 Question 9]], [[Questions:Limb Evolution#q3|June 2025 Question 30]]
 | Level2 = Identify the explanation based on evidence that evolution is the result of genetic and/or environmental factor(s) or justify why the given explanation is correct or incorrect.
-| Example2 = [[Questions:Zebra Coat Patterns#q3|January 2026 Question 43]]
+| Example2 = [[Questions:Star of the Tide Pool#q1|August 2026 Question 1]], [[Questions:Honeybee Behavior and Threats#q4|January 2026 Question 31]], [[Questions:Zebra Coat Patterns#q3|January 2026 Question 43]], [[Questions:Evolutionary Relationships Biology#q2|August 2025 Question 34]], [[Questions:Keratin – A Very Versatile Protein#q5|August 2025 Question 28]], [[Questions:Dinosaurs Evolution Sample Cluster#q1|June 2025 Question 1]], [[Questions:Drinking Water Is Just The Beginning!#q2|June 2025 Question 7]], [[Questions:Heads or Tails?#q2|June 2025 Question 12]]
 | Level1 = Identify the evidence, from those provided, that supports the explanation that evolution is the result of a genetic and/or an environmental factor.
-| Example1 = [[Questions:Limb Evolution#q5|June 2025 Question 32]]
+| Example1 = [[Questions:Green and Black Frogs#q2|June 2026 Question 11]], [[Questions:Baboon Evolution#q2|January 2026 Question 34]], [[Questions:Limb Evolution#q5|June 2025 Question 32]]
 }}

@@ Line 193: / Line 193: @@
 | Level4 = Construct an explanation based on evidence that the process of evolution primarily results from four factors: (1) the potential of species to increase in number, (2) the heritable genetic variation of individuals in a species due to mutation and sexual reproduction, (3) competition for limited resources, and (4) the proliferation of those organisms that are better able to survive and reproduce in the environment.
 | Level3 = Construct an explanation based on evidence that the process of evolution can involve: (1) the potential of species to increase in number, and/or (2) the heritable genetic variation of individuals in a species due to mutation and sexual reproduction, and/or (3) competition for limited resources, and/or (4) the proliferation of those organisms that are better able to survive and reproduce in the environment.
 | Level2 = Identify the explanation based on evidence that evolution is the result of genetic and/or environmental factor(s) or justify why the given explanation is correct or incorrect.
 | Level1 = Identify the evidence, from those provided, that supports the explanation that evolution is the result of a genetic and/or an environmental factor.
 }}

@@ Line 73: / Line 73: @@
 | style="background-color:white;" | [[Questions:Dinosaurs Evolution Sample Cluster#q1|Question 1]]
 |}
 == Vocabulary ==
@@ Line 196: / Line 187: @@
 * selection pressure (environmental pressure) – implied by "competition for an environment’s limited supply of the resources"
 </div>
 == {{Resourcesheading}} ==

@@ Line 1: / Line 1: @@
 {{Navlinks|HS-LS4-1|HS-LS4-3|← HS-LS4-1|HS-LS4-3 →}}
 {{learningstandard
 | ls = Construct an explanation based on evidence that the process of evolution primarily results from four factors: (1) the potential for a species to increase in number, (2) the heritable genetic variation of individuals in a species due to mutation and sexual reproduction, (3) competition for limited resources, and (4) the proliferation of those organisms that are better able to survive and reproduce in the
 environment.
@@ Line 16: / Line 16: @@
 ! style="padding: 0.5em 1.5em;" | Question
 |-
-| style="background-color:white;" | [[August 2026 Life Science: Biology Exam|August 2026]]
+| style="background-color:white;" | [[August 2026 Life Science: Biology Exam|August 2026 Biology Regents]]
 | style="background-color:white;" | [[Questions:Star of the Tide Pool|Star of the Tide Pool]]
 | style="background-color:white;" | [[Questions:Star of the Tide Pool#q1|Question 1]]
 |-
-| rowspan="4" style="background-color:white;" | [[June 2026 Life Science: Biology Exam|June 2026]]
+| rowspan="4" style="background-color:white;" | [[June 2026 Life Science: Biology Exam|June 2026 Biology Regents]]
 | style="background-color:white;" | [[Questions:A Seasonal Strategy for Survival|A Seasonal Strategy for Survival]]
 | style="background-color:white;" | [[Questions:A Seasonal Strategy for Survival#q5|Question 5]]
@@ Line 33: / Line 33: @@
 | style="background-color:white;" | [[Questions:Australian Adaptations#q3|Question 44]]
 |-
-| rowspan="3" style="background-color:white;" | [[January 2026 Life Science: Biology Exam|January 2026]]
+| rowspan="3" style="background-color:white;" | [[January 2026 Life Science: Biology Exam|January 2026 Biology Regents]]
 | style="background-color:white;" | [[Questions:Honeybee Behavior and Threats|Honeybee Behavior and Threats]]
 | style="background-color:white;" | [[Questions:Honeybee Behavior and Threats#q4|Question 31]]
@@ Line 43: / Line 43: @@
 | style="background-color:white;" | [[Questions:Zebra Coat Patterns#q3|Question 43]]
 |-
-| rowspan="4" style="background-color:white;" | [[August 2025 Life Science: Biology Exam|August 2025]]
+| rowspan="4" style="background-color:white;" | [[August 2025 Life Science: Biology Exam|August 2025 Biology Regents]]
 | style="background-color:white;" | [[Questions:Strategies for Survival in Different Animal Species|Strategies for Survival in Different Animal Species]]
 | style="background-color:white;" | [[Questions:Strategies for Survival in Different Animal Species#q2|Question 6]]
@@ Line 56: / Line 56: @@
 | style="background-color:white;" | [[Questions:Evolutionary Relationships Biology#q2|Question 34]]
 |-
-| rowspan="4" style="background-color:white;" | [[June 2025 Life Science: Biology Exam|June 2025]]
+| rowspan="4" style="background-color:white;" | [[June 2025 Life Science: Biology Exam|June 2025 Biology Regents]]
 | style="background-color:white;" | [[Questions:Drinking Water Is Just The Beginning!|Drinking Water Is Just The Beginning!]]
 | style="background-color:white;" | [[Questions:Drinking Water Is Just The Beginning!#q2|Question 7]]
@@ Line 69: / Line 69: @@
 | style="background-color:white;" | [[Questions:Limb Evolution#q5|Question 32]]
 |-
-| style="background-color:white;" | [[Biology Sample Questions|Sample clusters]] (Spring 2024)
+| style="background-color:white;" | [[Biology Sample Questions|Biology sample clusters]] (Spring 2024)
 | style="background-color:white;" | [[Questions:Dinosaurs Evolution Sample Cluster|Dinosaurs-Evolution]]
 | style="background-color:white;" | [[Questions:Dinosaurs Evolution Sample Cluster#q1|Question 1]]
@@ Line 231: / Line 231: @@
 | TOPIC = HS. Natural Selection and Evolution
 }}

@@ Line 7: / Line 7: @@
 | ab = Assessment does not include other mechanisms of evolution, such as genetic drift, gene flow through migration, and co-evolution.
 }}
 == {{Assessmentheading}} ==
@@ Line 88: / Line 74: @@
 |}
 == {{Dimensionsheading}} ==

← Older revision		Revision as of 02:22, 21 September 2026
Line 25:		Line 25:
	{{assessmentmessage}}		{{assessmentmessage}}

−	* [[Questions:Dinosaurs Evolution Sample Cluster#q1\|~~Dinosaurs Evolution Q1~~]]	+	{\| class="wikitable" style="width:100%; text-align:center"
		+	! style="padding: 0.5em 1.5em;" \| Exam
		+	! style="padding: 0.5em 1.5em;" \| Cluster
		+	! style="padding: 0.5em 1.5em;" \| Question
		+	\|-
		+	\| style="background-color:white;" \| [[August 2026 Life Science: Biology Exam\|August 2026]]
		+	\| style="background-color:white;" \| [[Questions:Star of the Tide Pool\|Star of the Tide Pool]]
		+	\| style="background-color:white;" \| [[Questions:Star of the Tide Pool#q1\|Question 1]]
		+	\|-
		+	\| rowspan="4" style="background-color:white;" \| [[June 2026 Life Science: Biology Exam\|June 2026]]
		+	\| style="background-color:white;" \| [[Questions:A Seasonal Strategy for Survival\|A Seasonal Strategy for Survival]]
		+	\| style="background-color:white;" \| [[Questions:A Seasonal Strategy for Survival#q5\|Question 5]]
		+	\|-
		+	\| style="background-color:white;" \| [[Questions:Green and Black Frogs\|Green and Black Frogs]]
		+	\| style="background-color:white;" \| [[Questions:Green and Black Frogs#q2\|Question 11]]
		+	\|-
		+	\| style="background-color:white;" \| [[Questions:Buzzy Bees\|Buzzy Bees]]
		+	\| style="background-color:white;" \| [[Questions:Buzzy Bees#q2\|Question 29]]
		+	\|-
		+	\| style="background-color:white;" \| [[Questions:Australian Adaptations\|Australian Adaptations]]
		+	\| style="background-color:white;" \| [[Questions:Australian Adaptations#q3\|Question 44]]
		+	\|-
		+	\| rowspan="3" style="background-color:white;" \| [[January 2026 Life Science: Biology Exam\|January 2026]]
		+	\| style="background-color:white;" \| [[Questions:Honeybee Behavior and Threats\|Honeybee Behavior and Threats]]
		+	\| style="background-color:white;" \| [[Questions:Honeybee Behavior and Threats#q4\|Question 31]]
		+	\|-
		+	\| style="background-color:white;" \| [[Questions:Baboon Evolution\|Baboon Evolution]]
		+	\| style="background-color:white;" \| [[Questions:Baboon Evolution#q2\|Question 34]]
		+	\|-
		+	\| style="background-color:white;" \| [[Questions:Zebra Coat Patterns\|Zebra Coat Patterns]]
		+	\| style="background-color:white;" \| [[Questions:Zebra Coat Patterns#q3\|Question 43]]
		+	\|-
		+	\| rowspan="4" style="background-color:white;" \| [[August 2025 Life Science: Biology Exam\|August 2025]]
		+	\| style="background-color:white;" \| [[Questions:Strategies for Survival in Different Animal Species\|Strategies for Survival in Different Animal Species]]
		+	\| style="background-color:white;" \| [[Questions:Strategies for Survival in Different Animal Species#q2\|Question 6]]
		+	\|-
		+	\| style="background-color:white;" \| [[Questions:Strategies for Survival in Different Animal Species\|Strategies for Survival in Different Animal Species]]
		+	\| style="background-color:white;" \| [[Questions:Strategies for Survival in Different Animal Species#q5\|Question 9]]
		+	\|-
		+	\| style="background-color:white;" \| [[Questions:Keratin – A Very Versatile Protein\|Keratin – A Very Versatile Protein]]
		+	\| style="background-color:white;" \| [[Questions:Keratin – A Very Versatile Protein#q5\|Question 28]]
		+	\|-
		+	\| style="background-color:white;" \| [[Questions:Evolutionary Relationships Biology\|Evolutionary Relationships]]
		+	\| style="background-color:white;" \| [[Questions:Evolutionary Relationships Biology#q2\|Question 34]]
		+	\|-
		+	\| rowspan="4" style="background-color:white;" \| [[June 2025 Life Science: Biology Exam\|June 2025]]
		+	\| style="background-color:white;" \| [[Questions:Drinking Water Is Just The Beginning!\|Drinking Water Is Just The Beginning!]]
		+	\| style="background-color:white;" \| [[Questions:Drinking Water Is Just The Beginning!#q2\|Question 7]]
		+	\|-
		+	\| style="background-color:white;" \| [[Questions:Heads or Tails?\|Heads or Tails?]]
		+	\| style="background-color:white;" \| [[Questions:Heads or Tails?#q2\|Question 12]]
		+	\|-
		+	\| style="background-color:white;" \| [[Questions:Limb Evolution\|Limb Evolution]]
		+	\| style="background-color:white;" \| [[Questions:Limb Evolution#q3\|Question 30]]
		+	\|-
		+	\| style="background-color:white;" \| [[Questions:Limb Evolution\|Limb Evolution]]
		+	\| style="background-color:white;" \| [[Questions:Limb Evolution#q5\|Question 32]]
		+	\|-
		+	\| style="background-color:white;" \| [[Biology Sample Questions\|Sample clusters]] (Spring 2024)
		+	\| style="background-color:white;" \| [[Questions:Dinosaurs Evolution Sample Cluster\|Dinosaurs-Evolution]]
		+	\| style="background-color:white;" \| [[Questions:Dinosaurs Evolution Sample Cluster#q1\|Question 1]]
		+	\|}

@@ Line 36: / Line 36: @@
 | DCI1 = LS4.B: Natural Selection
 * Natural selection occurs only if there is both (1) variation in the genetic information between organisms in a population and (2) variation in the expression of that genetic information – that is, trait variation – that leads to differences in performance among individuals.
 | DCI2 = LS4.C: Adaptation
 * Evolution is a consequence of the interaction of four factors: (1) the potential for a species to increase in number, (2) the genetic variation of individuals in a species due to mutation and sexual reproduction, (3) competition for an environment’s limited supply of the resources that individuals need in order to survive and reproduce, and (4) the ensuing proliferation of those organisms that are better able to survive and reproduce in that environment.