this is techknow. this is a show about science by scientists. tonight, techknow journeys into the jungle. this is one of the iconic animals of costa rica. >> how extensive is the damage? we are going to find out.

>> we're going to walk every trail, stream, or swamp we come across to see what's out there. >> i'm phil torres. i'm an entimologist. >> ready? >> yes. >> i'll share it with a biologist. that's our team. now let's do some science. hey, guys, welcome to techknow. you guys know, i've spent a lot of in the jungles. i do my research in the tropics and usually i'm looking at spiders and butterflies. but this time i went down to costa rica to look at something

different. we know there are a lot of scientific issues out there protecting our rain forest is one of them certainly but maybe it's not quite high enough on the list. because we're realizing now that rain forests are doing incredible services for us in society. >> and they're doing them for free. completely for free. we don't usually think about ecosystems like rain forests providing fundamental services. >> it takes so much to keep new york running, so many systems, the rain forest is so much more complex. >> what's amazing is those services that you see in the rain forest, they don't just stop there. they're actually affecting us here in los angeles and that's something scientists are just now beginning to realize. let's take a look. >> if you listen closely, you can hear the lyrics, the poetry of the rain forest.

among its trubadors is this guy. literally, you see post cards with this thing. here's looking at you, kid. check out these farm hands working dusk 'til dawn to cultivate their garden. stunning beauty unparalleled by adversity. the magic that is the rain forest. i travel to costa rica to check out the health of these ecosystems. these tall, dense jungles are known for warm climates, lots of rain, and sheltering more than half of the world's plant and animal species. although rain forests comprise a small

percentage of the earth, they do big things. in human terms, they're a critical component to how we function. >> i love to think of the amazon, the rain forest as the lungs of the planet. >> they're more like the heart of the biosphere. our tale of the rain forest brings us to nasa's jet propulsion laboratory in pasadena, california where scientists use all different techniques to understand our living, breathing, green earth. a recent study reveals tropical rain forests may be man's best friend. >> what our study shows is that the tropics really dominate the metabolism of our planet. they dominate the removal of fossil fuels from the atmosphere. they're really cleaning up the

planet. >> their research-employed satellite mapping, forestry data, and good old fashioned jungle gum shoeing. trees like these are natural consumers of carbon monoxide which leads to global warming. their research suggests rain forests are absorbing far more co2 than previously reported. >> if they're not taking up carbon, the simple answer is there would be 25% more carbon in the atmosphere than there actually is and the rate of warming would be approximately 25% faster. they're helping to regulate our climate. >> despite an overall decline in the destruction of rain forests over the past decade, it's still a story of paradise lost. farming, construction, pollution, and drought.

just to name some of the threats to these incredibly complex ecosystems. understanding and documenting the life in these forests is like taking their pulse. >> so we just got into the bat cave and it is absolutely amazing. length of those antenna are incredibly long which tells you that this thing is specifically adapted to living in the dark. >> what do we have inside? >> we got insects and -- wow, some of these are amazing. look at that. a mosquito in there. that's the best looking one i've ever seen. >> like his nasa colleagues, the senior scientist spends most of his time in and around global forests. >> there used to be a term in the 70s and 80s, the hamburger effect. meaning all these forests were being deforested for grazing animals.

now it's actually the soy bean effect. you're actually reducing the bio diversity of the world a lot. >> but the trees appear to be fighting back, and a global movement is underway to offer financial incentives to not degrade these rain forests. some places in the world are getting the message. >> costa rica is kind of a good example. they're kind of one of the green countries in the world if the. >> we're heading there next to the deep jungle. i heard there might be vampire bats in there. >> join the conversation by following us on twitter and at al jazeera.com/techknow.

while rain forests around the world continue to be diminished, there's a bright spot in costa rica. this is a 720 acre rain forest that once was partly devastated by pasture use. planted. >> today, through impressive environmental efforts, it's a shining example of reforestation and renewal of biodiversity. paul foster is the founder. >> most of the trees we're looking at here we planted 12 years ago. originally this was pasture. regenerated. >> i like your garden. it's very nice. >> as an

entamologist i got a chance to discover new species and check out how the animals are doing. the rain forest comes alive at night. we are going to walk every trail, swamp, or water we come across. this is a unique animal of costa rica. you see post cards with this thing. take a look. >> this is a postcard. >> wow. that's incredible. it's right now one of the things we're looking now are glass frogs. they're bright green frogs and the bottom is see through which is why they're called glass frogs. this is it. what are we looking at? >> laying eggs. and if it doesn't rain a few days, he'll urinate or water the eggs so that they don't dry out.

>> that's a caring father for you. indicating creatures like glass frogs are sensitive to pollution and other things and are a good barometer of the environment. it's a time stamp. the next day the search for species continues in the most mysterious of places. paul is taking me to a cave in the middle of the rain forest and we heard there might be v van -- vampire bats in there. >> you going first? >> yes, sure. oh, good. >> bats get a bad rap but in real life, they're an important

part of our ecosystem. khalil is a real life bat man and studies them. >> they eat bugs, eat nectar, eat pollen. >> i never worried about being attacked by a bat but entering this cave was daunting. i keep telling myself that it's all for science. >> the bat cave is absolutely amazing. i'm drenched and covered in mud but there are probably about 50 to 100 bats. >> it's a little muddy in there but we saw some good stuff. >> the stream down there, we can clean up a bit. >> yeah. >> back in the rain forest, a

critical part to understanding its condition is knowing what's living in there. take a close look at this butterfly, for example. at night you can find butterflies sleeping so i'm going to wake it up a little bit so i can show you guys. to us, it looks like an owl but to a predator, when you see it on the side, it actually looks something more like an lizard or a snake's head. you can tell looking at these parts in here that it's a male and they smell really distinctly, kind of like burnt ketchup which is really word. >> it's time to hit the books to found. bones. >> oh, yes. green bones. >> yep, there it is. >> so that tells us. wow.

some frogs have green bones. who would have known. >> uh-huh. >> what does it mean to you every time you can add a new species to your species list. >> it's just the process of discovery and the process of linking all of the organisms that live here together and learning more about their connections and interactions with each other. >> studying and documenting life in the rain forest is so extremely important for science. it is strenuous work and the conditions at times, hazardous. but often, the rewards are phenomenal. when you discover a new species for that reserve, what's the process? >> basically it's really important just to document it and say this species was found here and when. so that we know exactly the

condition of the rain forest at this time. this is relatively new reserve. there's others nearby this one in costa rica that have been documenting species for decades and using that data set, they're already seeing the effects of global warming. >> yeah, if you look at species through the optics of climate change, you know, the idea that species have their quote, unquote, natural ranges, but now that climate is changing, temperatures are warming, say, that's going to affect where these species occur, where they live, where they go. and in a place like where you were in costa rica where there's a lot of mountain ecosystems, those species are going up the mountains but what's going to happen when they reach the top. >> you see that in the rain forest but also here in the u.s. there are deferentery species -- definitely species being affected in the rocky mountains, for example. up next, a scientist who is

recycling pollution into works of art.

>> criminal gangs risking lives >> it's for this... 3 grams of gold >> killing our planet >> where it's blood red... that's where the mercury is most intense >> now, fighting back with science... >> we fire a laser imaging system out of the bottom of the plane >> revealing the deadly human threat >> because the mercury is dumped into the rivers

and lakes, it then gets into the food chain... >> that's hitting home >> it ends up on the dinner plate of people... >> techknow only on al jazeera america >> part of al jazeera america's >> special month long evironmental focus fragile planet this is al jazeera america life from new york city i'm tony harris. another day, another presidential candidate. marco rubio makes it official. captured on camera a white deputy sheriff, guns down a black man in tulsa. he says he meant to fire his taser instead. and one year later marking the abduction of hundreds of nigerian girls. br are they -- where are they and what has been done to save them? ♪