Variety is the Spice of Life

Unit 2: Ch 5 Variety is the Spice of Life – Biomes and Biodiversity

Description:

Scientists have discovered over 2 million species on earth, and there may be millions more left to discover – yet this is just 1% of the total number of species that have ever lived on earth! Why are there so many species of life, and how do they change over time? In this unit, we will examine the characteristics of the major types of biomes on earth and how species are adapted to live in each of them. We will also trace the history of life over time, focusing on how species are constantly affected by environmental changes.

Synthesis Question:

Why is there such great diversity in climates and lifeforms on Earth, both today and throughout history?

Packet Contents:

Chapter 5 Vocabulary List

Reading Questions 5A

• The Dung of the Devil
• Earth is home to a tremendous diversity of species
• Evolution is the mechanism underlying biodiversity.

1. What does the story of the “Dung of the Devil” tell us about the value of biodiversity?

biodiversity is important so the entire ecosystem or species does not disappear so easily. Increases resistance.

1. Many traditional societies (such as indigenous tribes of hunter-gatherers) have cultural traditions of using certain plants or animals as part of medicinal treatments. How can we determine which ones actually have an effect, and which ones are mere superstition?

It has to be tested with and without placebo. If it works in both cases then its works.

1. How do each of the following types of biodiversity support healthy ecosystem function:
   1. Genetic diversity – creates higher resistance and allows ecosystem to sustain dmg
   2. Species diversity – allows species to survive environmental changes
   3. Ecosystem diversity – allows environment to sustain damage and organisms

1. What is the current estimate for the total number of species on Earth, and why is it so hard to get an accurate count?

7 Million, many aren’t discovered and some are changing and new ones are coming.

1. What is the difference between species richness and species eveness?

Richness is the abundance of one species and evenness is the diversity of species.

1. Which one do you think is more important for ecosystem health – species richness or eveness? Explain.

Eveness because it brings diversity and this creates a stronger ecosystem.

1. How do scientists construct a phylogeny, or phylogenetic tree?

This is done by tracing back the heritage of organisms and species.

1. Explain how genetic diversity is created through evolution.

Evolution increases variety of animals that can survive ecosystem and environmental changes.

1. In artificial selection, humans induce evolution in a species over time through our actions. Provide 2 examples NOT from the textbook of how humans can shape species’ evolution.

They can affect it indirectly by destroying habitats and also by polluting it unintentionally.

1. What factors dictate changes in species in the process of natural selection?

1. List 5 organisms and describe the adaptations that increase their fitness in their environment:
   1. Sting rays, with stingers to fight off predators
   2. Bees, with stingers to fight off larger enemies
   3. birds with different beaks changing to what they do
   4. Monkeys with opposable thumbs to grasp
   5. Hedge hogs with pokey backs to ward off predators
   6. eagle with eyes close together to see better
   7. bunnies with eyes on the outside of their head to see predators

Complete the following chart regarding evolution through random processes:

Reading Questions 5B

• Speciation and extinction determine biodiversity.
• Evolution shapes ecological niches and determines species distribution.
• Working Towards Sustainability: Buying the Oceans?

1. Describe the process through which allopatric speciation can produce new species.

First the species must be split into two by a geographic feature, then they will adapt separately creating new species.

1. How can sympatric speciation occur if the individuals a population are not geographically isolated?

First there must be 2 distinct biomes or areas of living next to eachother. Then the species will adapt and create two different ones.

1. Why is the speed of environmental change a critical factor in determining whether or not a species can successfully adapt?

It has to be slow enough to where the animal has appropriate time to adapt and quick enough to actually impose a change.

1. How do a population’s size and genetic diversity influence its ability to adapt to change?

1. Suppose Population A is small and the species has a short generation time, while Population B is large and has a long generation time. Which will be faster to adapt? Which will be more resilient in the face of environmental change?

1. How do a species’ range of tolerance for various conditions determine its fundamental niche?

If they can't survive in a niche, they can't become a fundamental part of a niche.

1. Why don’t species always use their full fundamental niche?

They may not because they might not be able to because their species richness isn't full enough to use it all.

1. What are some of the major differences between niche generalists and niche specialists?

Niche generalist don't have a specific job, but have an important role in the ecosystem. Specialists have a specific role in the ecosystem which is less important.

1. How is global climate change expected to affect species distributions? How could scientists determine the likely effect on a particular species?

It could change the ecosystems and species fitting these range of tolerance will move there and those who don't will migrate.

1. The average lifespan of a species is just 1-10 million years. Why do you think there are such a high rates of speciation and extinction constantly occurring throughout the history of life on Earth?

This is because the earth is constantly changing and species aren't able to adapt quickly enough and also there are many natural disasters.

1. If extinctions are generally a result of changes in the environment that a species is unable to adapt to, what do you think this indicates about the 5 previous mass extinctions and the 6^th one occurring now?

I think these are occurring because of human actions and not because of natural actions and animals are becoming extinct for no reason.

1. What is The Nature Conservancy’s strategy for protecting rare species and areas with high biodiversity? Do you think it will be successful?

Nature conservancy uses money from people buying parts of the ocean to help save the environment.

1. Why are shellfish particularly valuable and particularly vulnerable in marine ecosystems?

They provide a high price and are a delicacy, also they are killed off easily by environmental change and invasive species.

APES Video Questions 5B

Watch “Crash Course Ecology 1: History of Life on Earth”

(http://www.youtube.com/watch?v=sjE-Pkjp3u4)

Read the Focus Questions in advance to help you catch key information. Take notes while watching, then summarize and answer the questions when you finish.

Focus Questions:

1. Describe what conditions were like on Earth ~4.5 Billion years ago when life began to form.

No oxygen, still very hot, many volcanoes, and soups of chemicals.

1. Why is RNA such an important molecule in early biochemistry?

It is the first genetic material.

1. What was the Cambrian Explosion? Contrast evolutionary trends & events BEFORE and AFTER the Cambrian Explosion.

Biological explosion in which the diversity of species increased dramatically with the help of eukaryotes.

Before the cambrian explosion, most species where just soft bodied worms and after many new adaptations came about with many different species.

1. What happened during the Permian Extinction, why is it important, and what happened afterwards?

No one can say what really happened in the event, but nearly all living animals in that time were killed off in one large event. Dinosaurs then came and evolved after.