Lecture 1An introduction

Principles of EcologyEben Goodale

College of Forestry, Guangxi University

Today’s class

• A mystery story: frogs with many feet!

• Science is providing explanations for mysteries.

• What is ecology? Some big picture ideas of ecology.

• Information about our course

• My background

• Why do you want to study ecology?

A mystery! （一个谜）In 1995, a school trip in Minnesota, USA found that 11 of 22 frogs they examined had major deformities. （畸形） News captured public attention:What was happening?More generally, why were Amphibian （两栖动物 ) populations declining?

Early observations

• Scientists started finding abnormalities back in the 1980’s.

• Found that many frogs contained Ribeiroia ondatrae （寄生虫） , a trematode flatworm parasite （一种变形性吸血寄生虫） .

• Produce cysts （生产囊肿） near developing limb buds…

• An early paper suggests that making such cysts (inserting beads) leads to limb deformities.

Observations and Experiment Pinpoint Ribeiroia （寄生性吸

虫）• Johnson et al. 1999:

– Surveyed 35 ponds, found only 4 with deformities, all those had the snail Helisoma tenuis, a host of Riberoira.

– Controlled experiment in lab with different levels of Riberoira.

Dashed line: frog deformitiesFull line: frog survival

Field experiment shows that causes of deformities may be complex （复

杂）• Could pesticides （农

药） be playing a role?

• Kiesecker et al. 2002 do experiment where frogs are measured for their susceptibility to Ribeiroia depending on pesticide levels in pond

3 ponds with pesticide, 3 ponds without.In each pond, frogsExposed or unexposed.

3 ponds with pesticide

ponds without

pesticide

%LimbDeform

Mass Of Frog

Black bars represent condition inwhich frogs exposed to Riberiroia

And even more complexity…• Johnson et al. 2007

show that excess fertilizer leads to more algae

more snails more Ribeiroia more frog

deformities

A case study to introduce our study of ecology

• Science is about explaining mysteries.

• Ecology is the science probing connections (or interactions（交互作用） ) between organisms and their abiotic and biotic environment.

Today’s class

• A mystery story: frogs with many feet!

• Science is providing explanations for mysteries.

• What is ecology? Some big picture ideas of ecology.

• Information about our course

• My background

• Why do you want to study ecology?

The scientific method

What’s wrongwith this picture?

Image from: http://scifiles.larc.nasa.gov/.

Scientific method• Identify question

– Why is this important to science / conservation / society / me

• Make hypothesis （假设）– Hypothesis leads to specific predictions Methods （研究方法）

• Gather data (experiment or observation)• Make conclusion• Communicate conclusion

– Community involved in review process– Science progresses through individual researchers contributing to

overall pool of knowledge (why do we want to do something novel?)

Kinds of Studies

• Descriptive.

• Observational. Looking for correlation between different variables.

• Experimental. Can more strongly suggest cause-and-effect.

• Modeling.

Which are scientific questions?• Are patterns of evolution consistent with the presence of God?

• Do babies prefer Coco Puff cereal to Fruit Loops?

• Are the fulvettas (a type of bird) a good taxonomic category?

• How many days do baby Orange-bellied Quetzals spend in the nest before fledging?

Take-aways:-Is the question testable?-Scientific questions not always very “heavy-weight”!-Some part of science is similar to other disciplines in that you need to make a reasonable argument (what is a good category? – it’s better than others)-Description is also part of science.

Experiments: Some Important Components

• Control Treatments（控制处理）

• Assign Treatments at Random （随机分配）

• Replication

• Statistical Analysis“X2 = 88.16, df = 3, P < 0.001”

The chance of this resultoccurring randomly is lessthan 1 in 1000

3 ponds with pesticide

ponds without

pesticide

%LimbDeform

Mass Of Frog

Black bars represent condition inwhich frogs exposed to Riberiroia

Today’s class

• A mystery story: frogs with many feet!

• Science is providing explanations for mysteries.

• What is ecology? Some big picture ideas of ecology.

• Information about our course

• My background

• Why do you want to study ecology?

A case study to introduce our study of ecology

• Science is about explaining mysteries.

• Ecology is the science probing connections (or interactions) between organisms and their abiotic and biotic environment.

Why “ecology”?• Eco

– from οίκος, oikos, "household"

• Logy– λόγος, logos, "knowledge"

Leafcutter Ants Nest

And these homes, too…

Big picture ideas

(1) It is a science about many different levels of organization （生态水平的组织）

From Molles (2008)

The Layers of Organization

• What’s not ecology?

Inside the individual: molecules organelles cells tissues organs

The Layers of Organization

• What’s not ecology?

BUT ecology is

related to these

layers …

Endosymbiotic theory

Of eukaryote cellLynn Margulis

The Layers of Organization

• What’s not ecology?

BUT ecology is

related to these

layers …

The ‘superorganism’

E. O. Wilson

Individual Organism （个体生物）

Deals with traits that the individual has, or behaviours it makes

How is this organism’s behavior, morphology （形态学） , physiology adaptive to its environment?

Population （种群）

Deals with the population … how large is it? How healthy is it?

A population is a group of individuals of one species living together at the same time and place. How is the number and reproductive status of the population effected by the environment?

Species （物种）

.

Ernst Mayr, the “biological species act”

All the individuals of all populations of a species. For our purposes, a species is a group of animals that is capable of breeding and producing fertile offspring

Species interactions

Specific interactions between species:Predator-prey interactions – food websCompetition among speciesParasitism (one positively affected, one negatively affected)Commensalism (one positively affected, one not affected)Mutualism (both positively affected)

Community ecology （群落生态学）

Now we’re beginning to compare different places (habitats or ecosystems) in the kinds of species present

Now more interested in the diversity of species in any one place … why is it low in some places/times, higher at others?

Ecosystem ecology （生态系统生态学）

Comparing places in overall function of the ecosystem (biomass made, nutrient cycling etc., fire resistance).

Landscape ecology （景观生态学）

How different ecosystems interact on the landscape

Global ecology

Evaluating world-wide problems such as global warming

Big picture ideas

(2) It is a science that spans a huge range of spatial and temporal scales. （跨越时间和空间的尺度）

The Sahel

A hive

Big picture ideas

(2) It is a science that spans a huge range of spatial and temporal scales.

Diurnal vertical migrationoccurs in ocean every day

Some ecologists are paleobiologists

Big picture ideas

(3) It is an applied science（这是一门应用科学） , and it must be applied, NOW

A restoration ecology class

Our class

Our learning objectives• To understand the principles of how organisms respond to your

environments, populations grow and go extinct （灭绝） , species interact through food webs and mutualisms, communities are structured, and ecosystems work as systems, cycling nutrients and energy.

• To learn about the environmental challenges that we will encounter in the coming century, and how ecological principles inform our solutions to mitigate and adapt to them.

• To be able to describe the ideas behind mathematical ecological theories using graphs, and to appreciate their predictions and assumptions.

• To sharpen listening skills, and interact in a classroom setting in

English.

Evaluation

• Comprehension test: no score but let’s you and me assess better how well you’re comprehending lectures.

• Midterm, final exam

• Attendance （到场）• Participation （参与讨论）

Schedule Lecture times:

Readings

• Textbook (recommended)

• Lecture Notes (required)

• Primary readings or homework assignments (required)

Cain, Bowman, HackerEcology2014 (3rd Edition)Sinaeur Associates

Most test questions will come from material covered in lecture and lecture notes. But there will be a few questions about primary readings, allowing you a choice in which you read.

My background

My teachers of ecology (your ‘grand-teachers’!)

Bill Bossert Peter Ashton

Sri Lanka

Sinharaja World Heritage ReserveA lowland rainforestImage from Uromi Goodale

Mixed-species flocks of birds

Primary leader Secondary leader

Following species

Experiments on Alarm CallsWho Talks to Who?

A twist to the story: drongo mimicry

The Crested Drongo:A vocal mimic

Image from Harsha Sathischandra

Mimicry attracts other birds towards drongos; reforms flocks

Drongos are multilingual

Then turned to what mixed-species flocking means to

conservation

Behavior (communication)influences flock structure,flock structure influencescommunity.

Forest

Buffer

Agriculture

How do flocks respond to differentlevels of land-use?

In China now for 2.5 yrs

At Xishuangbanna TropicalBotanical Garden, Chinese Academy of Sciences, until October 2014.

Continuing work on behavior, communities and conservation biology of birds.

Why do I consider myself an ecologist

Animal behavior.

Behavioral ecology: the roles of behavior in adapting an animal to its environment

Animal behavior Behavioral Ecology

Why do you want to study ecology?

What can we do with ecology?• Ecologists can be of many types, usually on

one level of organization (“behavioral ecologist”, “community ecologist”, “ecosystem ecologist”).

• They can be academic or engage in governmental or nongovernmental organizations.

What can we do with ecology?

• For example, ecologists work as:– In the park service, managing nature reserves.– In a public health institution, managing animal-

bourne diseases.

What can we do with ecology?

• For example, ecologists work as:– As a forester, assessing （评估） how best to

manage succession after logging.– In fisheries, figuring out how many fish to take in

order to have more the next year.

What can we do with ecology?

• For example, ecologists work as:– In private companies, providing reports about the

ecological impact of proposed developments (“consulting”).

– In schools and universities, teaching and research.

There are many kinds of applications of ecology

• Environmental science （环境科学） . Ecology is a key component, of the interdisciplinary area of environmental science (along with chemistry, geology, engineering, geography and law) that strives to understand and correct human impacts on the biosphere.

There are many kinds of applications of ecology

• Conservation ecology. To preserve what we have.• Restoration ecology. To restore ecosystem

function and biodiversity in highly disturbed areas• Resource economics. The study of efficient uses

of natural resources.

So why do you want to study ecology?

Homework

• Read through Syllabus and bring questions to class.

• Review: Lecture 1 notes.• Primary literature: Scan through Kiesecker et al.

(2002), particularly Figure 1. Be able to explain what experiment was done. What are the controls of this experiment (for pesticide, for Ribeiroia)?

Key Concepts

• Ecology is about connections among living organisms, and between them and their physical environment.

• We use the scientific method to identify a question, test a hypothesis, gather data and communicate results.

• Ecology as a science spans many levels of organization and scales in time and space.

• Ecologists work in many sectors of the economy and ecology as a subject can prepare you for different careers.