Unit 1: Reproduction

This unit will explore the topics of natural selection, bird vocalizations, courtship rituals and mating displays, nesting, and how reproductive success is measured. Students will not only be able to construct explanations and interpret data, but also understand more about the ecology of birds and begin “thinking like a bird” in terms of habitat and resource needs. For a summary of the lessons you can refer to the document posted below. If you have any questions feel free to email Education Coordinator, Paige Witek, at paige.witek@mrbo.org.

Lesson Topic: Introduction to Natural Selection

Lesson Theme: Organisms with traits better suited to their environment tend to survive and reproduce.

Missouri Science Standards: LS4.B.1

Natural Selection– The process of organisms changing over time. Organisms with traits better suited to their environment tend to survive and reproduce.


Variation– The different occurrences of the same trait among individuals of the same species (hair color, eye color, height, etc.)


Trait– A characteristic belonging to a population or organism.

Populations do not change. Shifts in population can happen in many ways. Some changes can happen slowly and take hundreds of years, like the gradual shift in traits from genetic change. Some changes can happen more quickly, such as a shift in population because of environmental changes like pollution.
Humans cannot control natural selection. Both plants and animals can be modified genetically by humans in a way that produces an organism with desired traits, but humans do not control natural selection. When humans modify a plant or animal genetically it is called artificial selection, and it is done for many reasons such as to create disease-resistance crops, bigger animals for food, and desired looks for specific dog breeds.
Environmental factors cannot change traits. Environmental factors can affect traits in both plants and animals. For example, the sunlight can affect the color of your skin, and it can also affect your health. Too much Sun exposure can lead to skin damage, but not enough can lead to a vitamin D deficiency.

Video Description: Video lesson covers all vocabulary terms and uses the Missouri example of the Oblong-winged Katydid to help describe the process of natural selection. Video is made by Missouri River Bird Observatory (MRBO) staff.

After watching video students need to complete this Google Forms Quiz to make sure they understand the concepts introduced in the video (Link is editable version of quiz). NOTE: Please make a copy of quiz before editing.

In this activity students will explore traits that help organisms be better camouflaged to their environment and how that increases their chances of survival and reproduction.

Teacher Notes:
• Preparation will take the most time for this activity (~ 25 minutes)
• Try to use easily biodegradable objects if the students choose an outdoor setting (which is recommended)

Video Instructions:

How does evolution really work? Actually, not how some of our common evolutionary metaphors would have us believe. For instance, it’s species, not individual organisms, that adapt to produce evolution, and genes don’t “want” to be passed on — a gene can’t want anything at all! Alex Gendler sets the record straight on the finer points of evolution. Video made by TED Ed.

After watching video students need to complete this Google Forms Quiz to make sure they understand the concepts introduced in the video. (Link is to editable version of quiz) NOTE: Please make a copy of quiz before editing.

Hank (Crash Course Teacher) guides us through the process of natural selection, the key mechanism of evolution. Video made by Crash Course.

After watching video students need to complete this Google Forms Quiz to make sure they understand the concepts introduced in the video. (Link is to editable version of quiz) NOTE: Please make a copy of quiz before editing.

Lesson Topic: Bird Songs vs Calls

Lesson Theme: A bird species’ song and calls have different characteristics and serve different purposes to enhance survival and reproduction.

Missouri Science Standard(s): LS1.B1

Songs – Tend to be complex, learned, and given principally by males in prolonged bouts in the breeding season to establish a territory and attract a mate.


Calls – Tend to be simple, innate, and used by both sexes in more general contexts, such as to raise an alarm, maintain contact between flock members, or beg for food.


Spectrogram – A computer- generated graph of sound frequencies across time. (or a way to visualize bird sound)


Frequency – The speed of the sound vibration, and this determines the pitch of the sound.


Amplitude – The size of the sound vibration, and this determines how loud the sound is.


Pitch – The quality of a sound governed by the rate of vibrations producing it; the degree of highness or lowness of a tone.

Bird species only make one type of sound or only have one song and one call. This misconception is often what can make learning the sounds that birds make so difficult. Almost all species of bird have more than one vocalization and some have repertoires into the thousands.
All individuals in a species will sound the same. Not all young birds copy songs from a tutor. Some invent their own songs according to the typical pattern of their species. In species that learn from tutors, some young birds typically end up with slightly different versions than their tutors sang. When birds breeding in a particular area sound similar to each other but different from members of the same species elsewhere, they are said to have a regional dialect.
Watch out for mimics. There are a few species of bird that will mimic other bird’s songs and calls and others who will copy only part of another’s song and include it in their own repertoire.
All bird sounds are innate. Some bird sounds innate, meaning that birds can produce them without ever having heard them before. The ability to produce innate sounds is inborn and genetically controlled. Some bird sounds are learned, meaning that in order to produce them properly, a young bird must hear them from an adult tutor of the same species. Tutors do not actively “teach”; instead, young birds learn by listening from a distance. The tutors are often the neighboring males on a young bird’s first summer territory. As far as we know, the only North American birds that can learn sounds are the hummingbirds, the parrots, and the passerines (excluding the flycatchers). Even in these groups, many sounds are innate.

Video Description: In this webinar, Ethan Duke, MRBO Director, leads a discussion of bird sounds, with a focus on how to identify and record your own.

Teacher Notes:

  • Video produced for MRBO webinar series so language will sometimes refer to birder terms and might be a bit advanced.
  • Start Video at 14:30 and End at 30:21. Total time: ~ 16 min.
  • If you want to make shorter you could cut out basic tone qualities from 19:37 to 26:14.
  • Video will include what sound spectrograms are, sound patterns and terms, basic tone qualities and key terminology.
  • Some bird recordings are on the quieter side so you may want to turn up volume for these parts.

After watching video students need to complete this Google Forms Quiz to make sure they understand the concepts introduced in the video. (Link is to editable version of quiz) NOTE: Please make a copy of quiz before editing.

Activity Summary: Students will use this excellent resource provided by Cornell Lab of Ornithology to learn more about how and why birds sing as well as learn the songs of a few bird species.

Teacher Notes:

  • Have students watch the 7-min video before doing the activity to learn what the game will involve and get some practice.
  • Then have the students move through the All About Bird Song interactive lesson to learn about how and why birds sing. The lesson will then lead them right into the game.
Video Instructions
All About Bird Song Tutorial

https://academy.allaboutbirds.org/features/birdsong/songbirds-in-action

Lesson Topic: Courtship Rituals and Mating Displays

Lesson Theme: The courtship rituals and mating displays of birds are not only entertaining, but also teach us how natural selection can produce unique behaviors and physical features.


Missouri Science Standards: LS1.B1, LS4.B.1, LS2.C.2

Display Behavior – a fixed set of actions that carries a specific message. Although many display behaviors are used to attract mates (courtship behavior), some display behaviors have other purposes.


Competition – A symbiotic relationship between or among living things that compete for limited resources, such as food, space, shelter, mate, ecological status, etc.


Lek – In animal behavior, a lek is a communal area in which two or more males of a species perform courtship displays.

All bird species are monogamous. Most songbirds in North America will somewhat secretly mate with multiple birds. DNA paternity testing shows that in many species, 40 percent of the young are the result of extramarital mating.
Birds pair for life. Splitting up is a regular part of life for almost all birds. Most live with one partner for only a few months or years depending on the species. Annual divorce rates range from 99 percent in the greater flamingo to 0 percent in the wandering albatross.
All bird species mate during the same month of a year. We typically think of spring as the mating season for birds, however, this period falls over several months with some birds starting as early as January, while others don’t start until the late summer months.

Video Description: This video lesson covers why birds use courtship rituals and the different types of display behaviors. It also addresses common misconceptions and vocabulary terms. Video is made by Missouri River Bird Observatory (MRBO).

After watching video students need to complete this Google Forms Quiz to make sure they understand the concepts introduced in the video. (Link is to editable version of quiz) NOTE: Please make a copy of quiz before editing.

Article Summary: Audubon writer, Hannah Waters, presents ten birds with interesting and outrageous courtship dance displays. Article includes videos of the displays as well as a fun, short description.

Article with Video Links: https://www.audubon.org/news/10-outrageous-ways-birds-dance-impress-their-mates

Teacher Notes:

  • Have students become familiar with some of the funkiest mating displays and courtship rituals by reading the article and watching the associated videos.
  • The follow-up questions will address what the students should takeaway from the article

After reading the article students need to complete this Google Forms Quiz to make sure they understand the concepts introduced in the video. (Link is to editable version of quiz) NOTE: Please make a copy of quiz before editing.

Activity Summary: Students will learn more about a unique species endangered in Missouri, the Greater- Prairie Chicken. They will examine the causes of this decline and design the ideal habitat with all the necessary components.

Teacher Notes:

  • Make sure students have all the necessary papers including the activity instructions and the Fact Sheet
  • An extension could be to have the students further research Greater Prairie- Chicken habitat management plans and compare them to their own design.
Additional Materials Needed for Activity

Lesson Topic: Nesting Cycle

Lesson Themes:
• Nests are important structures for young survival.
• Nest types and materials vary widely depending on species and habitat.

Missouri Science Standards: LS1.B1, LS2.A.2

Clutch Size – The number of eggs laid in a single brood by a nesting pair of birds. Some species of birds will lay only one or two eggs while others will have clutch sizes to as many as 20.


Brood – The group of young produced or hatched at the same time. Some species of bird will only have one brood in a year while others may have multiple. When species have multiple broods, some will re-use the nest and others will make a completely new one.


Incubation – The act of sitting on the eggs to keep them warm to allow them to hatch.


Incubation Period – The period over which eggs are incubated by a parent. In general, birds do not begin incubating until the clutch is complete and the incubation period is defined as the period from the laying of the last egg of the clutch until that egg hatches.


Nestling Period – The number of days between hatching and leaving the nest or fledging.


Fledge – To leave the nest.


Brood Parasitism – A form of social parasitism practiced by certain birds, such as cuckoos and cowbirds, in which eggs are laid in the nests of other birds, causing them to be hatched and the young reared by the hosts, often at the cost of the hosts’ own young.


Parasitism – A type of symbiotic relationship between two species in which one member, the parasite, benefits at the expense of the other, the host, sometimes without killing the host organism.

Birds use nests all year long. Birds only use nests as a place to incubate eggs and raise young. Once chicks fledge, adults and young do not typically continue to use the nest. However, some birds will return to the same general areas to nest year after year.
Cowbirds are a pest species that should be eliminated. Cowbirds are a brood parasite, meaning they lay their eggs in nests of other species. Baby cowbirds grow fast and can crowd out other chicks. This is an example of a species using an alternative reproductive strategy. Cowbirds are native to the United States and therefore are protected by law, so it is illegal to harm them. Some birds are able to recognize and reject cowbird eggs.
Two parents are needed to raise the young. In many birds like hummingbirds and woodcock, the female raises the young all by herself. In other birds like crows and blue jays, parents recruit nannies, usually former offspring, to help protect and feed the young. There is a lot of variability on how and who raises the young and makes the nest based on species.

Video Description: This video lesson covers why birds make nests, the nesting cycle and brood parasitism. The connection between nest type and habitat is emphasized. Video is made by Missouri River Bird Observatory (MRBO).

After watching video students need to complete this Google Forms Quiz to make sure they understand the concepts introduced in the video. (Link is to editable version of quiz) NOTE: Please make a copy of quiz before editing.

Video Description: This video is a clip from MRBO webinar, “Bird Nesting: Family Edition” and it covers the different nest types and gives examples of each.

Teacher Notes:

  • Watch from 5:47 to 32:44.

After watching video students need to complete this Google Forms Quiz to make sure they understand the concepts introduced in the video. (Link is to editable version of quiz) NOTE: Please make a copy of quiz before editing.

Activity Summary: Students will gain appreciation for the skill and work required to make a well-structured bird nest by taking on the role of bird parent to construct their own nest using the materials they have at hand. They will then put their nest through a few tests to determine the structural integrity and quality of their nest for maximum egg and nestling survival.

PBS Video: The Structural Engineering of Nests (Described in instructions)

https://kmos.pbslearningmedia.org/resource/nat15.sci.lisci.structnest/the-structural-engineering-of-nests/

Video Description: Watch the busy hummingbird craft the perfect nest in this video from NATURE: Animal Homes. The female hummingbird plays the role of surveyor, architect and builder in her effort to create a suitable home for her eggs and future chicks. Video is from PBS.

Video Link: https://kmos.pbslearningmedia.org/resource/nat15.sci.lisci.humming/hummingbird-surveyor-architect-and-builder/

Teacher Notes:

  • Video is 2 min and 28 sec in length.
  • Even though the species mentioned and shown is a Anna’s Hummingbird, the Missouri (Eastern) species, the Ruby-throated Hummingbird, makes a very similar nest and has a similar process.

After watching video students need to complete this Google Forms Quiz to make sure they understand the concepts introduced in the video. (Link is to editable version of quiz) NOTE: Please make a copy of quiz before editing.

Lesson Topic: Measuring Nesting Success

Lesson Themes:
• One way we can measure reproductive success is by measuring nesting success.
• We can use long-term nest monitoring data to see how specific factors may increase or decrease nest success.

Missouri Science Standards: LS2.A.1, LS1.B2; LS2.C.2
Missouri Math Standard(s): 7.DSP.A.1a-c

Nest Success – MRBO determines a successful nest to be a nest that has completed the full nesting cycle through the fledging stage. Another way to state this would be to say that a successful nest is one for which at least one young bird fledges (or leaves the nest).


Data – Factual information (such as measurements or statistics) used as a basis for reasoning, discussion, or calculation.


Methodology – A particular procedure or set of procedures. The methodology employed in an experiment is essential to its success, and bad methodology has spoiled thousands of research projects. So, whenever a piece of research is published in a scientific or medical journal, the researchers always carefully describe their methodology; otherwise, other scientists couldn’t possibly judge the quality of what they’ve done.


Sample Size – Sample size is a count the of individual samples or observations in any statistical setting. For example, in the MRBO nest monitoring study there is currently a sample size of 667 nests. Though a relatively straightforward concept, choice of sample size is a critical determination for a project. Too small a sample yields unreliable results, while an overly large sample demands a good deal of time and resources.


Target Species – Target species are species or species groups specifically chosen for long-term monitoring studies. The target species are chosen based on the goals of the study.

Video Description: This video is Part 1 of a two-part interview with Missouri River Bird Observatory’s (MRBO) Grasslands Project Leader, Erik Ost. During Part 1 of the interview, we cover MRBOs Grassland Bird Nest Monitoring Project including what we are studying, why we are studying grassland birds, and how we gather data. The video also covers most vocabulary terms. Video is made by MRBO.

After watching video students need to complete this Google Forms Quiz to make sure they understand the concepts introduced in the video. (Link is to editable version of quiz) NOTE: Please make a copy of quiz before editing.

Activity Summary: In this activity students will examine real-life nest monitoring data from the Missouri River Bird Observatory’s Grassland Nest Monitoring Project. They will learn how to interpret graphs and tables as well as use this information to construct a scientific explanation for how environmental factors influence the growth of organisms.

Teacher Notes:

  • Supporting materials include 2019 MRBO Nest Monitoring Report
  • Report Scavenger Hunt worksheet is also included to help the students navigate this technical report. Answer sheet included in packet.
Additional Documents Needed for Activity:

*Email paige.witek@mrbo.org for Report Scavenger Hunt Student Worksheet answers.

Video Description: Interview Part 2 with Erik Ost, MRBO Grasslands Project Leader. In Part 2 of the interview we cover what MRBO does with the data collected, how land managers and other entities use the data and how students can provide their own data to help birds through community-science projects.

After watching video students need to complete this Google Forms Quiz to make sure they understand the concepts introduced in the video. (Link is to editable version of quiz) NOTE: Please make a copy of quiz before editing.

Student- Led Option

This version of the unit allows students to access all the lesson components on their own remotely. It contains all the necessary video links, google quizzes, and documents the students will need to do each lesson. This option would be ideal for teachers who wish to leave the lessons as they are and have students that are learning remotely or who have access to internet capable devices in the classroom. Please contact Education Coordinator, Paige Witek, at paige.witek@mrbo.org if you have any questions about the Student- Led Option hosted through Tutor LMS.