APES Chapter 9.1 Species Extinction

Summary

In Chapter Nine, the focus is on sustaining biodiversity and examining the impact of extinctions on humanity. The chapter delves into the honeybee population decline since 2006, known as colony collapse disorder, and its significance in pollination. It discusses the current extinction rate, which is a thousand to ten thousand times faster than the natural background rate, driven by human activities such as habitat loss and climate change. The video also covers the concepts of endangered and threatened species, highlighting the ecological 'smoke alarm' these statuses represent, and mentions several species at risk of extinction.

Takeaways

• 🐝 Chapter 9 focuses on sustaining biodiversity and the impact of extinctions, particularly using the honeybee population decline as a case study.
• 📉 Honeybee populations have been in sharp decline since 2006, a phenomenon known as Colony Collapse Disorder, affecting pollination of crops.
• 🌱 Commercial beekeepers truck hives to farms to support pollination, but have been experiencing losses of 30-40% of their stock annually.
• 🌐 Biodiversity is crucial as over-reliance on a single species can lead to significant problems, such as the current honeybee crisis.
• 🚨 Species are becoming extinct at an alarming rate, potentially a thousand to ten thousand times faster than the historical rate, largely due to human activities.
• 🌿 Habitat loss, climate change, and ocean acidification are highlighted as major causes of the increased extinction rates.
• 🌎 The current extinction rate is believed to be at least a thousand times higher than the natural background rate, with estimates suggesting over a hundred species going extinct each year.
• 🔍 Biodiversity hotspots like rainforests and coral reefs are at higher risk of extinctions due to their high biodiversity and ongoing degradation.
• 🏞️ Fragmentation of habitats, such as cutting through forests for development, can lead to isolation and problems for species movement.
• 🐯 The script discusses the difference between endangered and threatened species, with the former being at immediate risk of extinction and the latter having declining numbers but not yet critically endangered.
• 🌳 Species with specific niches, slow reproduction rates, or large territory requirements are more vulnerable to becoming endangered or extinct.

Q & A

What is the main focus of Chapter Nine in the context provided?

Chapter Nine focuses on sustaining biodiversity, examining the causes and impacts of extinctions, and exploring what can be done about it.

What is the 'colony collapse disorder' mentioned in the script?

Colony collapse disorder refers to the significant decline in honeybee populations and colonies since around 2006, which has been a cause for concern due to their crucial role in pollination.

How important are honeybees to pollination in the United States?

Honeybees pollinate approximately 71% of the vegetable and fruit crops in the United States, highlighting their vital role in agriculture.

What is the current trend in honeybee population according to the script?

The script indicates that there has been a decline in honeybee populations due to colony collapse disorder, with commercial beekeepers experiencing losses of 30 to 40 percent of their stock each season.

What are the potential causes of colony collapse disorder in honeybees?

The script suggests that potential causes could include factors such as certain fungi, pesticides, and other environmental stressors.

Why is it problematic to rely heavily on a single species for biodiversity?

Relying on a single species can create a significant problem if that species faces a crisis, as it can lead to a collapse of the ecosystem services it provides.

What is the current rate of species extinction as discussed in the script?

The script states that species are becoming extinct at least a thousand times faster than the historical rate, and it could be as much as ten thousand times faster.

What are some of the human-related causes of extinction discussed in the script?

Human-related causes of extinction mentioned in the script include habitat loss, climate change, and ocean acidification.

What is meant by the 'background rate' of extinction?

The 'background rate' of extinction refers to the natural, ongoing extinction rate that occurs due to normal environmental changes and is estimated to be about one species per million species per year.

What is the significance of the term 'mass extinction' as used in the script?

A 'mass extinction' refers to the extinction of many species over a relatively short geological period of time, which is currently believed to be influenced significantly by human activities.

What are 'biodiversity hot spots' and why are they important?

Biodiversity hot spots are areas with exceptionally high biodiversity, such as rainforests or coral reefs. They are important because they are areas where extinction rates are projected to be much higher than average, and they represent significant ecological value.

What does the script suggest about the future of extinction rates and ecosystem services?

The script suggests that the rate of extinction and threats to ecosystem services are likely to rise sharply in the next 50 to 100 years, which could impact the services that nature provides for human survival.

Outlines

00:00

🐝 Chapter Nine: Sustaining Biodiversity

Chapter Nine focuses on the importance of sustaining biodiversity, particularly through the lens of honeybee population decline, a phenomenon known as colony collapse disorder. Since 2006, honeybee colonies have been in sharp decline, affecting pollination services crucial for both vegetable and fruit crops. Commercial beekeepers often rent out colonies to farmers for pollination purposes. The chapter delves into the causes of this decline, which may include pesticides and other environmental factors. It emphasizes the dangers of relying too heavily on a single species for ecosystem services and encourages biodiversity as a more sustainable approach.

05:03

🌿 Mass Extinction and Human Impact

Paragraph two discusses the concept of mass extinction, highlighting that current extinction rates far exceed the natural background rate, potentially by thousands of times. It points to human-related causes such as habitat loss, climate change, and ocean acidification as significant factors. The paragraph also touches on the historical causes of mass extinctions, like asteroid impacts and volcanic activity, and contrasts these with the current human-driven factors. It emphasizes the rapid pace of habitat destruction and degradation, the role of human lifestyle and consumption, and the projected increase in extinction rates and threats to ecosystem services within the next 50 to 100 years.

10:04

📊 Estimating Extinction Rates and Species Status

This paragraph explores the challenges in estimating extinction rates due to the slow and gradual nature of natural extinction processes. It discusses how scientists observe habitat loss and its impact on extinction rates to make current estimates. The distinction between endangered and threatened species is clarified, with endangered species being at immediate risk of extinction and threatened species being at risk of becoming endangered. The paragraph serves as an ecological 'smoke alarm,' indicating that a decline in species numbers signals a problem within the ecosystem that requires attention.

15:07

🐾 Factors Leading to Endangerment and Extinction

Paragraph four examines various factors that contribute to species becoming endangered or extinct. It covers reproductive strategies, with K strategists like the blue whale and giant panda being particularly at risk due to their low reproductive rates. It also discusses the vulnerability of species with specialized niches, narrow distributions, high trophic levels, fixed migratory patterns, rarity, commercial value, and large territory requirements. The paragraph provides specific examples of endangered species, such as the Mexican gray wolf, California condor, whooping crane, and Sumatran tiger, emphasizing the urgency of conservation efforts to prevent their extinction.

Keywords

💡Biodiversity

Biodiversity refers to the variety of life on Earth, including the variety within and between species and ecosystems. It is the main theme of the video, as it discusses the importance of maintaining biodiversity and the consequences of its decline. The script mentions that relying too much on a single species can create problems, illustrating the importance of biodiversity for a balanced ecosystem.

💡Extinction

Extinction is the disappearance of a species. It is a central concept in the video, which discusses current extinction rates and their causes. The script explains that species are becoming extinct at a much faster rate than the natural 'background rate', largely due to human activities such as habitat destruction.

💡Honeybees

Honeybees are used as a case study in the video to illustrate the impact of extinction. They are crucial for pollination, and their declining population due to 'colony collapse disorder' since 2006 is a significant concern. The script mentions that honeybees pollinate about 71% of vegetable and fruit crops in the United States, highlighting their importance to agriculture and food security.

💡Colony Collapse Disorder (CCD)

Colony Collapse Disorder is a phenomenon where worker bees from a beehive abruptly disappear. It is mentioned in the script as a reason for the decline in honeybee populations since 2006. CCD is a significant issue because it directly affects pollination services that are vital for crop production.

💡Ecosystem Services

Ecosystem services are the benefits that humans obtain from ecosystems. The script discusses how mass extinction can affect these services, which include oxygen production, clean water, and food. The video emphasizes the importance of preserving biodiversity to maintain these essential services for human survival.

💡Habitat Loss

Habitat loss is the reduction or destruction of habitats where species live. It is identified in the script as one of the main causes of the increased extinction rate. The video explains how human activities, such as converting forests into farmland, contribute to habitat loss and the subsequent decline in biodiversity.

💡Climate Change

Climate change is a long-term change in the average weather patterns. The script mentions it as a factor contributing to extinctions, particularly by altering habitats and causing species to migrate or become extinct if they cannot adapt to the new conditions.

💡Endangered Species

Endangered species are those that are at risk of extinction. The script discusses the difference between endangered and threatened species, with endangered species being at an immediate risk of extinction. The video uses the example of the honeybee to illustrate the concept and the urgency of conservation efforts.

💡Threatened Species

Threatened species are those whose numbers are declining and are at risk of becoming endangered. The script explains that threatened species are still numerous enough to survive, but their populations are decreasing, and they require monitoring and protection to prevent their decline into endangerment.

💡Mass Extinction

Mass extinction refers to the extinction of many species in a relatively short geological period. The script discusses the current situation as a potential mass extinction event due to human activities, which are causing extinction rates to far exceed the natural background rate.

💡Biodiversity Hotspots

Biodiversity hotspots are areas with a high diversity of species and high levels of endemism. The script mentions that these areas, such as rainforests and coral reefs, are experiencing higher than average extinction rates due to human activities like pollution and habitat destruction.

Highlights

Chapter nine is a companion to chapter four, focusing on extinctions and their impact on biodiversity.

Honeybee population decline since 2006, known as colony collapse disorder.

European honeybees pollinate about 71% of US vegetable and fruit crops.

Commercial beekeepers truck hives to farms to rent colonies for pollination.

30-40% decline in honeybee stock due to colony collapse disorder.

Dangers of relying too much on a single species for biodiversity.

Species extinction rates are currently a thousand to ten thousand times faster than the historical rate.

Human-related causes are accelerating extinction rates.

Natural background rate of extinction is about one species per million species per year.

Current estimates suggest we are in a mass extinction event.

Human population and resource consumption are major causes of habitat destruction.

Biodiversity hot spots like rainforests and coral reefs are at higher risk of extinction.

Coral reefs are degraded by pollution and ocean acidification.

Rainforests are being cut down for croplands, leading to habitat loss.

Estimates of extinction rates are challenging due to the slow nature of natural extinction.

Endangered species are at risk of imminent extinction, while threatened species are declining.

Regional extinction refers to species no longer found in areas they once inhabited.

Functionally extinct species have lost their interaction with other species.

Animals with low reproductive rates, specialized niches, or fixed migratory patterns are more vulnerable to extinction.

Commercially valuable species like rhinoceros are at risk due to poaching.

Large territorial requirements make species like the Florida panther vulnerable to extinction.

Several large animal species are critically endangered, such as the Mexican gray wolf and the California condor.

Transcripts

[Music]

foreign

hey guys welcome back here we are

for chapter nine

in chapter nine it is really sort of a

companion chapter

to chapter four i usually sort of teach

them together

so if you're looking at this chapter

truly independently

it's worth a look at least at the

extinction parts in

chapter four chapter nine sustaining

biodiversity what we're really going to

look at

are extinctions how do they affect us

and what can they do about it primarily

for this chapter we're going to kick

right off with the core case study

where have all the honeybees gone

as we know the honeybee population has

been declining since really about

2006 where they've even given it a name

the colony collapse disorder we have

seen the

european honeybee populations and

colonies

in really sharp decline now

this is obviously important because they

play such a key role

in pollination here in the united states

the european honeybees pollinate about

71

of the vegetable and fruit crops we tend

to think of them as

going by flowers but a lot of our

vegetables corn etc

actually have blooms which need

pollination now commercial bee keepers

actually

truck hives out to certain farms

a lot of farmers literally rent the bee

colonies

so a beekeeper brings the colonies out

to this

farmer's orange grove out to this corn

crop out to somebody growing cucumbers

you name it strawberries so they rent

this particular species of beef

and they bring out but we have been

seeing

about 30 to 40 percent of their stock

go down it's the colony collapse

disorder enough bees go and that entire

colony that's in one of the little bee

things collapses that is gone

they lose them they've been losing 30 40

of their stock every season

it's an issue it's a danger now we'll

look at it a little later but there's a

lot of reasons for it whether it's some

fungus whether it's

pesticides being used other things that

they're running into

but it is dangerous to rely this much

on a single species biodiversity tends

to wind up working

better for everybody when we rely too

much on one species

then it can create a huge problem

but honeybees one of these things that

we are

looking at and tracking and realize it's

an

issue now section 9.1

which we're hitting today is really

species

extinction once again a lot of overlap

from chapter four

so here we go species right now are

becoming extinct

at least a thousand times faster than

the historical rate

and it could be as much as ten thousand

times faster

than the historical rate once again

faster than this background

extinction and a lot of these are human

related causes which we're going to get

into in this chapter we're going to look

at habitat loss

climate change and ocean acidification

as some of these reasons

now extinctions are natural

but sometimes they increase

very sharply so it is a natural process

it's going on

all the time and we talk about the

background rate so the background rate

of extinction this is just what

is happening going on normal for

whatever reasons the normal habitat

changes in climate forest fires

volcano erupts disrupts an area just

happens

is about one species

per million species so for every million

species out there on the planet at any

given time

about one species go extinct a year now

we're unsure but we think there are

about 10 million

species on the planet so that'd be about

10 species

going extinct a year so if 10 species 10

12 15 8 that's just background

what we expect when the rate rises above

the background that's where we kind of

want to look around and go hey

what's happening what's going on

what we really believe we're in right

now is a mass extinction

event because we are well beyond

the background rate so a mass extinction

is extinction of many species in a short

period of time

now a short period of time can be

thousands

of years you know when we're looking at

fossil record and several hundred

million years ago and hey we don't find

any below this

it's not an overnight process it's still

hundreds if not thousands of years

but the past causes of mass extinction

events have where they're largely

unknown we feel pretty confident about

165 million years ago

was a large asteroid lots of data to

back that up

and evidence from it but many of the

others really are unknown it can be

multiple volcanoes can be other

asteroids comet

changes in the climate but something to

cause them

they've normally we believe been caused

by

large global changes in the

environmental

conditions you know once again where the

asteroid hit

rose up a dust cloud that blocks out a

lot of the sun so many

plants die off once again global change

cools off

sun doesn't get through disrupts the

food chain etc

but these mass extensions have always

been due to

environmental conditions if you will

now currently human population

are destroying and degrading habitats

at a rapid pace well once again think

about going and creating a farm

we cut down the trees to turn it into a

farm we cut down the grasslands to turn

it into a farm

we spray the pesticides to get the bugs

away so that our farms

yeah we're changing and degrading

the habitat so our huge resource

consumption

just our lifestyles in general in the

united states

have a large ecological footprint

we want lots of things these things have

to be made provided

harvested etcetera and because of that

our extinction rates have risen

sharply very recently once again

our best estimates are the current

extinction rate is some

thousand times higher than the natural

background rate

100 would be 10 species 200 percent

would be 20 species a year

300 30 you know we think we're at

more than a thousand times higher than

the natural back rate

at least 100 species a year and it could

be

a lot more this rate of extinction

and threats to our ecosystem services

are likely to rise very sharply in the

next 50 to 100 years

your lifespan remember ecosystem

services that are

those are all the things that nature is

providing for us

oxygen clean water basic

food that we need lively many of things

that we rely

on are happening in nature out in the

rural areas

most of us live in urban areas but we're

dependent on the ecosystem services from

the rural so this is what we are

worried about the mass extinction may

have an effect on

our ecosystem services the things we

need for survival

now there's a lot of biodiversity hot

spots

out there like the rain forest or a

coral reef

they just tend to have really high

biodiversity

and these are the places where

extinction rates are projected to be

much

higher than average we've seen our coral

reefs get degraded from

sometimes it's tourists going and being

in them so much

a lot of it's been pollution and

acidification

of the oceans because of the fossil

fuels we burn

creates higher levels of acid in the

ocean

we know with the rainforests we've been

cutting them down so that we have

croplands etc biologically diverse

environments

are being eliminated entirely or

highly fragmented remember fragmentation

is simply where we take a forest

and we cut a swath through it there's

still forests here and we have farmland

or housing

and we have another little forest here

used to be one big forest

well now it's fragmented and things

can't get from here to over there

and it can cause problems now

we're estimating that our extinction

rate is a thousand times above

background noise background extinction

rate

but there are problems with estimating

because natural extinction this

background

it's a long process once again it

doesn't happen

overnight unless we know there's this

one type of owl that only lives in this

type area we cut all the trees down

but as a general rule a species going

extinct is a long process you know the

numbers dwindle they get lower lower

eventually done or left so it's

difficult to document

our fossil record doesn't document

everything we don't have fossil record

of

every living thing but when we see like

these large

animals that we can recognize say like

the tiger

not around anymore those we can see

so a lot of times we kind of focus on

the ones that we can see and notice more

clearly

so we've only identified about two of

the seven

to ten million species on the planet

earth

and we know very little about the

ecological roles

of most of the identified species we

have

we've talked about some of these

keystone species

like the american alligator or the otter

and many of these species we don't

really realize the ecological niche that

they really

occupy and how important it is until

they're gone

obviously with honeybees we realize if

there were no more honeybees

our pollination rates would sharply

decrease so some things we know but

maybe

we don't so our approach is

to observe how reductions in a habitat

area affect extinction rates

and then estimate the current rates so

if we

know if we eliminate the things in this

area

what would happen then we look at how

much habitat we are

actually removing and we begin making

estimates because we know if we remove

this habitat

what would happen and then we look at

habitats that are being removed

and we have to begin to make some of our

estimates

there's problems with it it's not

perfect it might be a little high it

might be a little low

but we've gotten pretty good at these

estimates

now let's talk about endangered species

versus

threatened species now first off any

time that we see an endangered or

weak market endangered or threatened

this is an ecological

smoke alarm if this animal is going

extinct

why what's the problem there's a problem

with the ecosystem

otherwise they wouldn't be going extinct

so anytime we see the numbers of a

particular animal especially something

we can

see dwindling getting smaller and

smaller and smaller

it's a smoke alarm where there's smoke

there's fire

what's the problem so an endangered

species

we label it endangered if there are so

few

members of that species that they could

become

soon extinct and otherwise if we don't

do something

they probably will become extinct

a threatened species there are still

enough numbers

or individuals to survive

that their numbers are declining and if

the numbers keep declining

then we would move them into endangered

there are simply more

protections for an endangered animal

than a threat

but when an animal becomes threatened we

realize it could become endangered and

we really start trying to watch and pay

attention and do what we can

before it makes the endangered species

look so

just the difference between endangered

the biggest problem

threatened because after endangered

it's simply extinct we can get things

that are either

regionally extinct or functionally

extinct regionally extinct means

it is extinct in areas that it's

normally

found let's take something like the

tiger it once used to roam a

huge swath of lands

now it's restricted to very small areas

and a lot of times even preserves wild

elephants they used to roam most of

africa but now you only find them in

certain areas

so we could talk about them being

regionally extinct they used to be here

but they're not

the elk up in the appalachians have

become regionally extinct

elk aren't extinct but they are not

found in the appalachians anymore they

were hunted

out of existence now they have brought

in

from manitoba a new population of elk

which are thriving but once again they

were driven to extinction

regionally we can also talk about

something being

functionally extinct it's the point

where the interaction with other species

are lost have been greatly diminished

the white rhino it's functionally

extinct the last male is gone we have

two females but

it's time it's almost gone now that's

extreme

functionally extinct but when the

numbers get so small

they're not going to be able to make it

in the wild they're functionally

extinct we may still have them for a

very short period

but we'll see now

let's look at some of these animals and

why

where they are coming extinct so i'm

going to throw the picture up here

and we'll take a look at them there are

a lot of different reasons why certain

animals

come on this endangered or threatened

species list

there's certain reasons the first one up

there the blue whale

well this represents blue whale giant

panda rhinoceros they all

all have this same feature they

are uh k strategists once again their

reproductive style

is low reproductive rate

they give only birth to a few organisms

and they're very

long spaced apart they may not have a

you know they may have one calf and it's

two three years later before they have

another so since they have such a long

slow reproductive rate

if their numbers dwindle they're in

specific danger of extinction

the giant panda has such a specialized

niche when something has to survive only

on one type of food or one particular

area well if that thing becomes

threatened the animal becomes stretched

so things in a very specific

niche are more likely to become on a

threaded endangered species a narrow

distribution

uh like the elephant seal or the desert

pup

fish we only find them in this little

little teeny tiny area so that habitat

gets destroyed

or threatened they tend to get

the things that feed at really high

tropic levels it shows a picture of an

eagle could be eagle hawk these tertiary

consumers

something that's eating plants you're

pretty safe and then the thing

that's eating the thing that eats the

plants but the higher you go

up so i have a primary consumer

and herbivore i have a secondary

consumer

so we have the grasshopper eating the

grass i have the bird eating the

grasshopper but when i have a bird

eating the bird it's feeding at such a

high tropic level

that they become endangered things like

eagles tigers

bears or such like these it says it

shows a sea turtle

fixed migratory patterns where they

always migrate in the same way if the

climates change

the problem happens in the habitat they

become issues

some things are just very rare like the

african violet

now we can get them in homes and grow

them but in the wild

they're incredibly rare those are some

orchids as well the ghost orchid in

florida

very rare only happens in a little tiny

area in some swamps

if they are commercially valuable

rhinoceros rhinoceros largely went

extinct

because of cutting off its horn

rhinoceros horn was used in a lot of

homeopathic type things it was seen as

that being a

sign of strength and virulence to eat

rhino horn powder etcetera and then

also things that just require very large

territories

like our florida panther virtually it's

functionally extinct there's so few of

them because they require such large

territories as humans spread

and we cut out where they can live not

many of them around

anymore so these guys are

smoke alarms now this last one up here

we're just going to look at a handful of

large

animals if you will that have very

little left the mexican gray wolf

there's only about 114 of them left in

the arizona

mexico area the california condor

now we have about 300 of them in the

wild now

but back in 1986 there were only nine

left they were all captured

brought in they did breeding techniques

and they've been releasing them back

into the wild

through up to 300 but still very very

few

the whooping crane north america we

think it's only about 400 or so left

and also the cement sumatran tiger

there's a lot of different

tigers siberian title bengal tiger

sumatran

so off the island of sumatra in

indonesia

only about 400 of these left in the wild

a lot of these large animals we're going

to watch in our lifetime

if we're not very careful go extinct

that is it for section one

join me next time for section two when

we look at

why do we care take care guys we'll see

you next time

you