5 Human Impacts on the Environment: Crash Course Ecology #10

Hank gives the rundown on the top five ways humans are negatively impacting the environment and having detrimental effects on the valuable ecosystem services which a healthy biosphere provides.
Table of Contents
Ecosystem Services 00:51
The Importance of Biodiversity 04:07
Deforestation 06:42
Desertification 06:49
Global Warming 07:59
Invasive Species 08:51
Overharvesting 09:20
Crash Course/SciShow videos referenced in this episode:
Hydrologic and Carbon Cycles: • The Hydrologic and Car...
Nitrogen and Phosphorus Cycles: • Nitrogen & Phosphorus ...
Ecological Succession: • Ecological Succession:...
Climate Change: • Climate Change
Invasive Species: • Invasive Species: The ...
Food Shortage: • The Bacon Hoax & the N...
References:
www.fs.fed.us/ecosystemservice...
www.endangeredspeciesinternati...
www.epa.gov/acidrain/effects/s...
Crash Course is on Patreon! You can support us directly by signing up at / crashcourse
Want to find Crash Course elsewhere on the internet?
Facebook - / youtubecrashcourse
Twitter - / thecrashcourse
Instagram - / thecrashcourse
CC Kids: / crashcoursekids

[@Alyssa-wz8mx]

Anyone else here 7 years later for online classes?

[@llp7722]

Any1 else hate bts

[@Alyssa-wz8mx]

😂

[@stellac8160]

yes lol

[@derpyderp1144]

Ye

[@3amigos949]

BTS Lover29 hahaha yes

[@ghostcat611]

Anyone watching in 2024

[@thetandlcorner5010]

_"Tina here. If you have no idea which one's are the 5. here!"_ Deforestation 5:37 -6:55 Desertification 6:56 -7:41 Global warming 7:42 - 8:44 Nonnative species 8:54 - 9:20 Overharvesting 9:21 - 9:42 _"If I am incorrect, tell me! Like if you want everyone else to see this!"_ EDIT: _"Guys I know it's in the description but not everyone checks that, so here it is in the comments."_

[@edgarn8084]

FriskPony you’re the goat🐐

[@stellac8160]

omg thanks so much

[@davidsarpong8042]

your a life saver thanks so much :)

[@jadeemerge3770]

tysm now i can do all my work lmao

[@isabella-em3rt]

life saverrr

[@NataliaSchenone]

wow this video has been up for 10 years , and we're living out everything he's explaining. At greater rates.

[@bencorey8315]

Hey! Biology teacher here: I always enjoy your videos, Hank, but this series on Ecology has been my favorite! Your masters in Environmental Science shows through your passion.

[@babbletron8730]

hey ben its me, jack. I think you are stupid and should stop teaching.

[@kai-zi9st]

mann this is awesome. I admire how passionate he is.

[@mjlock7338]

can we get a whole separate segment for environmental science?

[@sunitamahadik7746]

Find out more about

[@awesomeloren8174]

YESSS

[@markocegn452]

hello MJ Lock I saw your comment and see that you care about the environment and the climate therefore I wonder if you are open to see what we do and help us together do something concrete to improve the environment?

[@Damouse007]

The key is "few hundred thousand years." As he says in the video, the things we have been doing and the things that are happening are taking place at an astoundingly fast pace.

[@biamenezes7801]

This is an amazing video and I'll surely watch this again. The part when you show the deforestation in the Amazon rainforest was kinda sad to me, since the majority part is contained within my country.

[@josephmorgan1595]

Who else has to watch this for there biology class?

[@rex7248]

what are you talking about everyone here is from trigonometry

[@josephmorgan1595]

Oh.

[@Moni.moni98]

+Eevee in a hat (Nature Mage) Me lol xd

[@user-qw1xe1fj8y]

me~

[@josephmorgan1595]

:3

[@Assasiinzz]

Its my Bio 4 exam on Friday and this show is so helpful for revision, im lucky to have it at the same time as my exams, thank you John and Hank

[@viptechies1843]

Imagine watching this again and realize that the Amazonian Forest is almost gone due to extreme wildfire. And imagine how many biodiversities were eradicated due to that phenomenon.

[@chococookies4]

The plants will grow back due to secondary succession. The plants always get replaced, but the animals are who I am grieving for.

[@777anouchka]

Would you be able to make a video on the possible mitigations or human interventions that can help the ecosystem, the benefits this could do or the harm it could possibly do?

[@savannahmeachum7027]

I enjoy crash course videos more than other videos when learning or reviewing for things that they also happen to cover

[@ashleygonzalez6119]

Wow, this is such a great video. I learned that humans have caused so many problems to happen such as littering, cutting trees and etc. If we had to do what the environment does for us as of today it would take us longer and a lot more time. The ecosystems are a combination of old and new things that create the environment we are in as of today.

[@mikem274]

Lmao definitely another depressing yet entertaining and insightful episode of Crash Course. Thank you Hank!

[@LookForwardtoLifeHeisTheLife]

Thank you for this 'basic' education on the problems that we (humanity) have caused. WE ALL NEED this info to understand the problems and, their poss solutions. PLEASE keep up the good work ! Keep spreading the news and, assisting mother Earth in such ways. TY !

[@amoolaassad4701]

Tom. Iam having biology exam and u really helped me in taking few IMP points that may help mee.. Really thank u ❤️👏

[@amylowis4595]

People who don't study Biology or Ecology should be required to watch this video

[@amylowis4595]

+COOL GUY111 in defence of myself, this photo is 3 years old

[@theguywholovespie2118]

+Amy Lowis They should be required to watch it every day for a month.

[@theguywholovespie2118]

How about... no. :P

[@amylowis4595]

Hey woah calm down everyone

[@theguywholovespie2118]

Amy Lowis RUN WHILE YOU CAN!!!!! XDD

[@a.t.akayoungdrew667]

"Thank you for watching another kind of depressing video of crash course ecology." 😂

[@pamelareinoso962]

My University should be cutting you a check bc my professor literally quizzes us on your videos

[@protectamericasconsumers4219]

All of these things are important for people to know whether you are a student or teacher. We have to be aware of what we are doing to the environment, for the long haul.

[@Shimamon27]

And how do you propose to make people care about anything other than their massive endless privileges? They want MORE not LESS. They will never give up their Hedonism, until there is nothing left to eat, and then they'll all enter into massive mental instability, and start killing each other by the masses. It'll be total carnage, and nobody will learn anything from the whole event. End of story, everybody loses.

[@sonokoluvr]

Mindeer it’s the sad reality

[@laurenfivecents]

thank you for helping me this year in biology! human impact is my last test this year, wooo!! i’ll be back for my final next week

[@Tornair]

I love these Ecology episodes! It reassures me that this is what I want to do with my life.

[@masieldlc12]

"why is this stuff turning the earth into sausage" XD. XD. XD

[@gaming_with_coral1705]

Masiel Delacruz that’s so funny XD XD 🤪😂🤣

[@miraculoustalesofobliviousness]

right?!?! like, i thought i was the only one who laughed out loud for that!!! XD

[@jessieclass741]

I wish everyone would watch this video. People don't realize how dependent we are on the environment. A lot of people think humans and nature are separate but that isn't true at all.

[@user-fi5fd2ky6e]

that is right. im sure alot of people know it is just that they dont have a reason to care...

[@jessieclass741]

True

[@ishouldbestudying251]

+Jessie Class Did you write this comment just because your teacher told you to?

[@jessieclass741]

Not at all. I wrote this comment because it's my honest opinion. I didn't even watch this for school, or because anybody told me too. I watched it because I honestly care about the enviorment.

[@ibizanhound7891]

Vegan Gains Actual Father What are you even talking about

[@mikaelboman5553]

Thanks for bringing youtube the best/most needed information out there! Cheers!

[@mariagordon-lewis2802]

Thank you for your videos...You got me through biology... Grade: A...Now I need you to get me through environmental science...core concepts of John Muir, Rachael Carson and Charles Darwin...If you can recommend certain videos to me --I would greatly appreciate...

[@EInc1000]

I'm addicted to these videos!

[@zhongliangcai602]

Ezra Grant , I only watch these because my mom tells me to XD.

[@then0un]

Hank, you mention cattle as the primary cause of deforestation (in the Amazon and globally) and desertification. I've been wondering if you're vegetarian. As a biologist, you know the industrial meat system is the single largest contributor to greenhouse gas emissions, deforestation, desertification, ocean acidification, use of petrochemical fertilizers/pesticides (for animal feed), use of arable land & fresh water, and the bulk of environmental problems we're wreaking upon this earth. As one who has studied psychology, why do you think people are so opposed to switching to a more sustainable plant-based diet? There seems to be a lot of resistance.

[@makaylamarshall9743]

Zortron culture, and it’s a really big overhaul to change one’s diet. I’m three years in still trying to change my diet and be primarily vegetarian

[@DrMurdockKawfi]

I feel like I need to mention that there are already logging restrictions in the rainforest. Nearly all the trees we use for lumber are grown on tree farms. The people cutting down trees in the rainforest are low income native populations who are trying to make farms and grow food for their families. If we help those people with better farming technology, less land will have to be cleared.

[@PontusWelin]

This isn't depressing! Not for me at least. It gives me a better understanding of these problems. And I NEED a better understanding. Please, please, please! Make more in depth videos about this subject!

[@DaehPhone]

In the midst of these walls of text, I would like to say I love this man's voice.

[@Nt3Hr]

Hi its 7 years later its 2020 now

[@highspacefox]

these last three are the best in the series! thanks for all the work yall do @ crashcourse, love yall!

[@crazyfett649]

I had to watch this for homework. I get what he is saying, but I almost fell asleep and I was counting down the seconds until it was over.

[@Shellewell]

When you said "we could never ever ever duplicate" my mind immediately went "getting back together."

[@centmilli]

watching all these from New Zealand. The presenter is awesome.

[@moaadm4620]

Thank you for helping me right my essay.

[@koofaya]

In Poland we have increased the total area of forests from 20% to around 30% since WWIII. So it's possible to do something good for the climate and quality of living while still being able to make good profit out of it. For an example, we make a lot of furniture for Ikea. Currently we're having problems with overpopulation of boars (300,000 of them) so reforestation is not only good for wood but also for food... =)

[@koofaya]

***** Yes, because we went to the future, seen all the shit, came back and planted loads of trees!

[@laramads5101]

WWIII? You from the future or something? XP

[@beatrizfitz8061]

Nerd

[@noahreed9091]

How does he talk for 10 minutes straight and keep his cool? I could never do that.

[@philiphan2145]

you do know that the video is edited right....

[@simoncolson6664]

nope he didn't

[@austinbevis4266]

Jump cuts

[@HelenaMaksyom]

Thank you so much for this video!

[@KelleyBelly459]

Great video Hank! To to the people calling him an "alarmist": it's called facts. People get all worked up over the economy, over healthcare... so why not the environment? There are just as many problems, if not more, that have to do with the environment. Frankly, the environment is the root of the poor economy, poor health, and almost everything else. So yes, you should be alarmed. You should be scared. And you should be excited to create solutions and care about your home.

[@talyah23]

And in August 2019 this video becomes incredibly sad that 6 years on we watch the Amazon being burned due to agriculture and our obsession with consuming meat/animals. We never learn and therefore deserve the extinction we are bringing on.

[@matthewdangelo8908]

i loved your video...i think the world needs more people like you...thanks a lot

[@NoelMarshall]

Great Presentation, Thank You, please keep educating for all our sakes.

[@xanomaly1]

Good idea on this two-parter! Thanks

[@michellelopez5264]

Have you done one on how we can fix these problems?

[@richardfrancis862]

I wonder what it's like now if this was in 2013. Also, who else is given an assignment with this for geo?

[@awddwa6544]

FACT: If all humans stop breathing, Earth will be saved.

[@supaboi9]

God: Oh my god! Why didnt I think of that!

[@nikispivey3316]

my 14 year old kid just started high school about a month ago and she has a environmental science class and she loves it

[@GowanRavin]

Hank & co - please please please do a video on what we as individuals can do to reduce the negative human impacts on climate change, be it by wasting less, changing habits, getting out and campaigning or whatever. I try to do as much as I can but I often feel I don't know enough about the related issues to act effectively, and I'm sure your knowledge base could provide some very helpful pointers to us all ^_^

[@Alfaneroruiz]

really liking it your videos!!!! Thanks a lot for uploading such nice videos.

[@WilliamLetzkus]

Excellent series!

[@ArmandoJustinChavez]

From the journal Earth System Dynamics billed as “An Interactive Open Access Journal of the European Geosciences Union” comes this paper which suggests that the posited AGW forcing effects simply isn’t statistically significant in the observations, but other natural forcings are.

[@ninjanerdstudent6937]

My lazy professor linked our class to this video as well as other videos.

[@theguywholovespie2118]

SAVE A COW, A FEW TREES, AN ECOSYSTEM. GROW A POTATO.

[@Shimamon27]

A kawaii potato~~~

[@theguywholovespie2118]

If you insist...

[@Shimamon27]

***** :3

[@jacobkleeman5708]

i like potatoes

[@uvraged9854]

I do grow potatoes.

[@jessd6359]

Thx, really helped me with my homework!

[@aaroncollier7984]

There is applied research that suggests significant grazing isn't damaging in all cases. In fact the lack of sufficient grazing herds can degrade the environment. I have linked a TED talk regarding this below. ted.com/talks/allan_savory_how_to_green_the_world_s_deserts_and_reverse_climate_change.html

[@LearnEnglishESL]

Good presentation... "We cannot segregate the human heart from the environment outside us and say that once one of these is reformed everything will be improved. Man is organic with the world. His inner life moulds the environment and is itself also deeply affected by it. The one acts upon the other and every abiding change in the life of man is the result of these mutual reactions." -Shoghi Effendi, Baha'i Faith

[@gaming_with_coral1705]

I love this thank you for your time and effort

[@gaming_with_coral1705]

I think I spelled that worng

[@alicethornburgh7552]

I went to Humboldt State University to study Environmental Science, and this is incredibly dumb... At 0:25 he says that human activity "could be" responsible for the extinction of "nearly" 1,000 plant and animal species in the last 100 years. The real numbers are way higher than that. "Scientists estimate that 150-200 species of plant, insect, bird and mammal become extinct every 24 hours. This is nearly 1,000 times the “natural” or “background” rate." Don't get me wrong, crashcourse makes some really cool stuff, I've seen it... But this guy made a 10 minute presentation on environmental science, and within 30 seconds he shows that he fundamentally misunderstands the magnitude of the crisis he's talking about. We're not just cutting down a few trees and changing the temperature a bit. We cut and burn 40 football fields of trees per minute. We redirect so much water and till so much soil that we have created deserts the size of countries. Misinformation like this makes me furious because it makes people think, "well if only 10 species a year have become extinct over the last 100 years, then maybe this is something we can solve next year if we just try a little bit harder. I'm sure that environmental group or whatever has it on lock..." People need to understand that by doing as much damage as we have, we have committed ourselves to fix it, and it's going to be expensive and controversial and it's going to take decades, and if we don't, this extinction event that we've created will continue to spiral out of control, decimating all the most beautiful things we know and love or want to discover. Want to know what happens when you cut down a very old tree? Here's a tree centuries old, and looks nothing like the other trees around it, and covered in a strange moss, and sweet smelling purple flowers. Only one species of bird in the forest is adapted to suck nectar from these flowers, touting a ridiculously long and otherwise impractical needle of a beak everywhere they go. When this tree falls, its flowers become extinct because they can only grow on that particular tree. The birds return to find the tree and its flowers dead, and they too become extinct... and the bugs that can only survive on the feces of the birds, and the fungus which only grows on the corpses of the poop eating bugs, and the bugs which only eat that particular fungus, and the spider which primarily eats the fungus eating bugs, and so on. The effects ripple through the forest, and hundreds or thousands of other species become extinct because of the felling of this one tree. You guys need to understand... We can't keep doing what we're doing and expect everything to be okay. Everything we love came from the rainforest- Chicken, bananas, strawberries, corn, wheat, prozac, marijuana, cocaine, opium, coffee, the list goes on- basically everything good comes from there, and what most people don't know is that's just the tip of the iceberg. We have yet to discover so much amazing food and medicine that exists in the rain forest, it would be a shame to lose it. Of course the rest of the world is also in jeopardy, but it isn't nearly as valuable, and I think this is the end of my soapbox. Look elsewhere for your education.

[@theguywholovespie2118]

YOU TELL 'EM

[@tarnyred1793]

Maybe he meant "thousands".

[@karimtabrizi376]

I think if people at least know the situation we all face that's a start. But if we idiots like Trump etc and OZ PM who deny this is an issue we are on a downward spiral.

[@apearl420]

Alec Thornburgh totally agree with you. We need to change our lifestyles and paradigms. Science and EIA should come before policy making but unfortunately it doesn't. Ex: the massive tar sands in Canada one of the worst planned irreversible environmental damage in the world under the Harper government.

[@noahreed9091]

Dang, this was more informative then the video itself.

[@lucas5530]

It's scishow dude! Thanks science teacher!

[@makaylamarshall9743]

And around the 4:30 mark, not only is biodiversity important, but functioning ecosystem cycles are also important. Gotta have all them carbon, nitrogen, and water cycles working together on top of high biodiversity for a fully intact ecosystem!

[@keldibekkozhoev2910]

thanks , this video helped me a lot on my project in school !!!

[@Imtortured]

I always thought desertification was when you got to the end of a meal and they brought you dessert and you where happy. Desertification.

[@pijushbhowal6214]

Really clear and appreciating explanation

[@nisbahmumtaz909]

Posting a video? Dude, he has a freaking master's in this stuff.

[@thechloeproject3514]

My teacher showed this video in class. It was good.👍

[@thechloeproject3514]

Just in case you want to know it's a 6th grade class.

[@erika-wp4ft]

Whut. I'm Year 1 and teacher also showed this in class.

[@claire5823]

...year 1?

[@keii2596]

The Chloe Project 😂

[@keii2596]

The Chloe Project 😂

[@emmystein]

I'm in university and I catch myself watching his science videos for fun....:p

[@1paupingson]

Hey! I just voted @TheCrashCourse in the shorty award! They deserve an award! :)

[@tonysintheattic]

True enough. This was actually a pretty enlightening chat.

[@pia_om]

haha awesome you guys did this so well :)!

[@detonatorJE]

please make a series on engineering!! :)

[@TheHarborRoseColdSpringHarbor]

Where is the Kami Link? Because i am using this video for school called West Side Elementary School

[@PreciousRareFind]

You're phenomenal Hank, thank you for the CrashCourse. You made it all easy to understand =D Every little bit of effort helps. Will you make a video of ways we can help the Ecosystem and Climate. Thanks...

[@thelastEnderBender]

thanks this is going 2 hlp me on my report.

[@Nt3Hr]

Cheese Whizard what did u get on ur report

[@VictoryDanDukor]

I love these. Yes, they're a bit depressing but at least I'm informed on the shit we're doing to the world.

[@tebwebweterikaua8272]

i really like this cuz it helps us what to solve any problems that our environment face

[@bigm240]

You get it

[@Biggreeniefun]

Brilliant video!+! "When I say 'effect', I don't mean in a good way." Hah hah hah. Yes, this video is definitely depressing, but it motivates us to fight these changes as much as we possibly can!-!

[@KoriKosmos]

It's nice to be surrounded by happy plants and critters doing their 'business'... sure Hank, if you're into that? o_O

[@LerriHelion33333]

Maan Meher Grow up.

[@KoriKosmos]

Lucas Hollands Do you honestly think that I care, its been 6 months and 8 days since I made this comment. Get a life before commenting on old posts.

[@LerriHelion33333]

Maan Meher I'll comment on whatever post I bloody well choose.

[@KoriKosmos]

Lucas Hollands Sorry, are you still there?

[@LerriHelion33333]

Maan Meher You have offended the culture of my people.

[@IsaacJennaithegenerous]

this needs 8 billion views.

[@akshayrathore2882]

or just 'muricans. no one else is debating global warming

[@martinandthegreenguitar5183]

Excellent video! Gotta show my kids!

[@Alitari]

Farmers and ranchers are perhaps one of our best and strongest advocates for environmental protection (in Canada, Alberta is considered 'dirty' for its oil sands, and yet it has some of the strongest environmental laws around other industries because of their heavy farming). The trouble with ranching is, as Hank mentioned, overgrazing. Regular farms keep plants in the ground, while overgrazing can result in no plants in the ground AND heavy hoof traffic, a dangerous combination if not managed.

[@DemirOmerSen]

6:06 so true 😂

[@martin_lopez9515]

Im seeing this in a class :D

[@alphacentaurus7972]

GIS and remote sensing and sustainable development too

[@lilianacarolinaaguirredi9a628]

See this video you can understand more about organisms and the enviroment

[@rainbowkat1516]

The environment is so strong yet so fragile.

[@fancymushroom.]

the environment is strong, but humans are way more stronger than our environment could ever be...

[@someone-ou3ht]

ecosystem is perfect and the imperfect humans are destroying it's perfection

[@alexbrown7890]

what about all the methane cows produce on that deforested land? doesn't that contribute to global warming?

[@theguywholovespie2118]

+Alex Brown It does. Possibly even more than the burning of fossil fuels...

[@swiftythegathering]

Great show. I teach an Environmental Science class and was wondering if you would mind if I showed your Ecology videos in class. Thanks in advance.

[@kirstenanoukborger]

This channel is great!!

[@shezthebestx3]

I think everyone in the entire world should watch this video. it's really sad First Nations came here 25 000 years ago, no TV's, no Computers, no picky eaters or anything. Pure Masculinity. Now, we, humans are single handedly destroying this world and not giving a damn. We should be ashamed we're abusing our intelligence for more landscaping. Don't even get me started about Asia. I know they want to have a son, and it's their religion but honestly we need to start not having children

[@chronofusion]

LOL. ok I'll put it just like George Carlin put it. And THINK for a second when you read this next statement WITH COMMON SENSE...mathematically...chronologically and historically. " The EARTH is NOT going anywhere. WE ARE.lol. This planet has been here for over 400 million years. Humans have been on this planet around 200 to 250 thousand. Do the math. This planet can shake us off like a mild case of fleas anytime it wishes. Earthquakes, tsunami's, hurricanes, tornadoes are all ways in which it does it." It cracks me up everytime I here people bowing down in fear thinking they are afraid they are effecting the lifeforce of this planet when we can't even combat against the planets methods of killing us. Some of us have the nerve to think we are a threat to this great 10 thousand mile wide ball of gases, and soil.

[@jennykapau4845]

chronofusion We are direct and indirect threats to innumerable living things on the planet; and some of us care deeply about them, in addition to how those changes will affect our species. I typically love George Carlin, even saw him in concert; but I hate it when people use that bit of his to mock the legitimate efforts of those of us who care deeply about life on this planet.

[@Aditya-wc9sw]

it's becos of some religion which wants to be the highest followed in he world Cough Islam cough

[@raeee204]

this guy is kinda savage- nice

[@Matrinique]

This needs more views....

[@thomasrocha4891]

See Allan Savory's TED Talk on reversing desertification. It was very enlightening, and was one of those things that seem so obvious after you hear it.

[@Official_Doge]

What I learned: cows ruin our land

[@kalexambing2507]

You should watch Cowspiracy. I think it's on Netflix.

[@Official_Doge]

+Kalexambing I need to watch food inc. too. I think we need to get rid of BPA and petrol based plastics, they're developing plant based biodegradable plastic

[@apearl420]

Doge no humans ruin everything.. cows do not originate from Americas they were transported by Europeans

[@Official_Doge]

apearl420 no I agree with that, since we domesticated cows lmao

[@noahreed9091]

Eh, "domesticated" is a little far. If I kidnapped a bunch of wolfs then made them do my bidding, is that domesticating them?

[@Alitari]

A recent thing I saw going around Facebook ... you show someone from the past an iPhone and say "With this device I can access entire libraries of knowledge from out of thin air ... and yet I use it to look at pictures of cats and get into arguments with people I will never meet."

[@sofiyachorniy]

For your 'cultural services' point, which you referred to as "less tangible", you may want to look into a book written by Richard Louv: The Last Child in the Woods. It's about the Nature-Deficit disorder, a term coined by Louv to describe the effects a lack of nature has on us as human beings.

[@SHEensya]

Crash course is awesome! Keep rockin’! 😍❤️❤️❤️