Do you drink coffee? A lot of people do—coffee is a major tropical crop, valued at over $100 billion per year. The most popular species of coffee, Coffea arabica, originated in Africa and is now planted extensively in Central and South America. The pest called the coffee berry borer beetle (Hypothenemus hampeii) moved along with the coffee and is a major problem for coffee farmers, sometimes destroying half of the coffee crop in mature plantations. Look at the graph.

Why did the researchers bother to collect data from the coffee shrubs before adding the nets to treatment plots to exclude birds?

Video transcript

Hi everyone. Welcome back. Let's look at our next problem. It says due to various human activities, forests are degraded and cleared out. Forests house a wide diversity of animals, from microorganisms to large animals such as elephants. Based on the following graph. What is the relationship between the size of protected lands and the number of species? So we're thinking about some habitat like a forest which has has a wide diversity of animals so many species. And saying due to human activities, sometimes these forests are destroyed which of course will reduce um you know destroy the habitat and reduce the number of species that are present because you just lost the habitat of so many species. So of course protected lands are when lands are protected from human activities. So the graph is asking us to look at what is the relationship between the amount of land that's protected and the number of species. So we see a number of species here on the Y axis, percentage of land and protection on the X axis. So we see this upward curve here telling us that as the percent of land that is protected increases the number of species also increases both increase at the same time. So we want to say, what is that relationship? And I'm going to scroll upward here to show us our answer choices. Well, when both increase so when among increases the other increases, we call that a positive association. So that's choice A Here they are positively associated. That is going to be our answer. But let's just see why the other answers are incorrect choice B says they are negatively associated. Well, that would be if you'd see when one increases the other decreases. So that's not what we have here. So that's not an answer choice C. They are not associated at all. But we have occurred. We have the shape. They were not associated. You wouldn't see any sort of shape there. You just see sort of a smattering of points. So that's not an answer choice. D. Says that data is not enough to make an interference, make an inference. Um But we do see this relationship clearly on the graph, so we do have enough data to make that inference. So that's not our correct answer. So again, based on the graph, what's the relationship between the size of protected lands and the number of species choice A. They are positively associated. See you in the next video.