Hank introduces us to the relatively new field of evolutionary developmental biology, which compares the developmental processes of different organisms to determine their ancestral relationship, and to discover how those processes evolved. Also fruit flies with eyes on their legs and chickens with teeth!

The video resource "Evolutionary Development: Chicken Teeth - Crash Course Biology #17" is included in the "Biology" course from the resources series of "Crash Course". Crash Course is a educational video series from John and Hank Green.

This "Evolution in Action" learning object is the from the Sumanas resource series. Sumanas offers a robust selection of content and services that are directed at enhancing the learning experience.

This article from AIR Worldwide is a brief history of the development of building codes in the United States and an explanation of their importance in estimating building stock vulnerabilities.The resource, "The Evolution of Building Codes in the United States with Respect to Hurricane Winds" included in "Lesson 01 Building Codes" is a part of "Unit 05 Green Sustainable Facility Design" included in Energy & Sustainability ES - Course 3.

Paul Andersen describes how cell communication is used in both single-celled and multicellular organisms. He starts by describing the symbiotic relationship between the bobtail squid and the bacteria Vibrio fisheri. He explains how bacteria use quorum sensing to communicate between each other and respond to changes in their environment.

This "The Evolution of Cellular Organelles" learning object is the from the Sumanas resource series. Sumanas offers a robust selection of content and services that are directed at enhancing the learning experience.

A hypothetical scenario is introduced in which the class is asked to apply their understanding of the forces that drive natural selection to prepare a proposal along with an environmental consulting company to help clean up an area near their school that is contaminated with trichloroethylene (TCE). Students use the Avida-ED software application to test hypotheses for evolving (engineering) a strain of bacteria that can biodegrade TCE, resulting in a non-hazardous clean-up solution. Conduct this design challenge activity after completion of the introduction to digital evolution activity, Studying Evolution with Digital Organisms.

Paul Andersen details examples of natural selection in the world. He starts by explaining how changes in global temperatures are causing plants to adapt. He explains how mutations cause changes in phenotype which give organisms varying levels of fitness.

Hank takes us on the fascinating journey through our excretory system to learn how our kidneys make pee.

The video resource "The Excretory System: From Your Heart to the Toilet - CrashCourse Biology #29" is included in the "Biology" course from the resources series of "Crash Course". Crash Course is a educational video series from John and Hank Green.

The primary purpose of this course is to render the invisible world of microbes visible to farmers. This course provides scientific-based instruction exploring how microbes can assist agriculture. Although the course is designed for farmers, this material can also help extension agents, curious citizen scientists, and other non-experts interested in enhancing their microbial literacy.

To evaluate the different integumentary systems found in the animal kingdom, students conduct an exploratory research-based lab. During the activity, students create a model epidermis that contains phosphorescent powder and compare the results to a control model. After learning about the variations of integumentary systems—systems that comprise the skin and other appendages that act to protect animal bodies from damage—students act as engineers to mimic animal skin samples. Their goal is to create a skin sample that closely represents the animal they are mimicking while protecting the base ‘epidermis’ from UV light.

The causes and consequences of global biodiversity loss and species extinctions are complex and rapidly changing across spatial and temporal scales. They have both local and global manifestations and are entangled with biological, socio-cultural, economic, and political processes. Many of these challenges demand novel approaches, including innovative research and interdisciplinary analysis. They need new skills and methods from various disciplines and expert communities, including the humanities, social sciences, and biophysical sciences. They also require rethinking who conducts research and communicates findings and how knowledge is produced at the intersection of research and higher education institutions and social change. 

This book aims to respond to these challenges. Extinction Stories was co-authored by undergraduate students at Worcester Polytechnic Institute, a private research university in Worcester, Massachusetts (USA), while exploring issues of extinction, environmental conservation, and biodiversity loss. The following twenty chapters combine the final projects conducted by students in the Great Problem Seminar (GPS) Extinctions course during the Fall of 2020 and the Biodiversity course in the Spring of 2021. Both courses took place while the world was still facing the impacts of the COVID-19 Pandemic—a global crisis that, as our current sixth mass extinction, is also profoundly rooted in long-lasting processes of habitat destruction and human-induced environmental change.

This text may also be accessed at extinctionstories.pressbooks.com/.

This "Extracellular Signaling" learning object is the from the Sumanas resource series. Sumanas offers a robust selection of content and services that are directed at enhancing the learning experience.

Mr. Andersen shows you how to use the factor label method to solve complex conversions.

A single lecture given at Kwame Nkrumah University of Science and Technology about bacterial vaginosis, HACEK infections, and legionella.

Watch how the blood flows through the fetal circulation and compare it to what happens in the baby's body. Rishi is a pediatric infectious disease physician and works at Khan Academy.

Although mom controls the oxygen source, the fetus has a couple of clever tricks to get the most oxygen possible! Rishi is a pediatric infectious disease physician and works at Khan Academy.

Find out what happens to those nifty fetal structures once we get older. Rishi is a pediatric infectious disease physician and works at Khan Academy.

Learn all of the different ways to maximize the amount of particles that diffuse over a short distance over time. Rishi is a pediatric infectious disease physician and works at Khan Academy. These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read or seen in any Khan Academy video.