Biodiversity | California Academy of Sciences
- Studying biodiversity in the lab
- How much biodiversity do we really know?
- The Journey of Mr. Sand Dollar: Systematics 101
- Test your knowledge: biodiversity analyses and unknowns
- Exploration questions: biodiversity analyses and unknowns
- Activity: biodiversity analyses and unknowns
- Glossary: biodiversity analyses and unknowns
- Selected references: biodiversity analyses and unknowns
- Answers to exploration questions: biodiversity analyses and unknowns
Created by California Academy of Sciences.
- [Narrator] How can a collection of natural history specimens inform us about biodiversity? How can an expedition result in information, not just about what things are out there and where they live, but how to protect them? What is it about the research that we do with museum collections that makes them unique and important? Why are they so precious? Here's a little story about a specimen chosen at random. Well, kind of at random. It's one of the organisms I study, a sand dollar collected from the Philippines. It's got this lovely, graceful shape to it with petal shapes on top and two holes towards the backend. We didn't collect the entire population. Though they are really hard to find, they can be really abundant in places. I collected as much data as I could when at the location, studying the sand dollars while they're alive, and then preserving the specimens to take back to add to the collections here at the academy. Back at the lab, we need to start the process of cataloging the specimen. So we take Mr. Sand Dollar here and we attach information to the specimen through a unique number known as a catalog number. That catalog number is linked not just to the specimen on the shelf but to what the specimen is, where it was found, any images taken in the field and all of that wonderful meta-data that are so crucial. Through this unique number we can always look up the data that are associated with that specimen. It's not a very complicated concept but it's one that's really central to the business of making sure those data don't get lost or separated from the specimen, kinda like making sure that the doctor doesn't lose track of your medical charts. If you had to list in order the most important pieces of information that you record about a specimen in a database, you would probably start with the location. Just where was it on Earth that you found it? In this day and age, you can do that through what's known as geo-referencing. We can use a specific geographic information system to record map coordinates that show where on Earth the specimen came from, sorta like pinpointing your position on your handheld smartphone. I also record the depth. I found these sand dollars in about six meters of water. I know because it was about the limit of my comfort for snorkeling ability. I might have also collected a sample of the sand they live in and can attach that information or any other special information related to the specimen. Notice I haven't said anything yet about what species the specimen is other than it's a sand dollar. Some idea of what it is, of course, is important but the actual species name is not the single most important piece of information for a variety of reasons. We can change our minds as we study it more or other experts come in and weigh in. Heck, it might even be a new species that doesn't have a name yet. But as long as we know where it's found and the circumstances under which it was found, we can still add to what we know about sand dollars and the biodiversity of the Philippines. Here's a slightly different example. Let's say instead of a single specimen like Mr. Sand Dollar, we gather a whole net full of different kinds of plankton. You could spend the rest of your life sorting through that one sample of plankton into all the different species and then giving a catalog number to every single one of the little guys. We take a simpler way instead and record this entire net full as a single collection, a single lot. It will still be useful to somebody later because, as usual, you have the locality data associated with that jar. A plankton specialist could still separate some individuals from the lot, but with that catalog number in place, we can always trace the data concerning the collecting event. We used to record catalog numbers in these creaky, old log books. Ledgers we called them. It's a fantastic ancient word for a fantastic ancient thing. Just write it down. Write a new number down and write what was associated with that number. These ledger entries were sometimes even typed, highfalutin technology in the 1940s and the 1950s, but today, of course, you can do that much more quickly, much more easily and I think with a lot more utility, of course, with this fantastic invention called the computer. You can enter data about a specimen under its catalog number, what you think it is, where it was found and so on, and then you'll be able to search that database and retrieve all of the information you have in the entire collection that's been cataloged. Going back to Mr. Sand Dollar from the Philippines, maybe at this point we can start wondering about his scientific identity. Is it a species we already know about? Is it brand new to Science? Can you get the great, "Ah-ha, I know what this is," now that you know that the data area safely recorded? You can get this ah-ha from just looking at the specimen. Sometimes you need to look at it very, very carefully. You look at its shape, its features, color, anything that helps you distinguish it from other species. This can happen with the naked eye, under a microscope, or with an electron microscope depending on the size of the organism or the size of its features. Studying the form or shape of organisms is called Morphology and it was the original tool used in identifying species. Now days, molecular techniques have been added to the toolbox of identification. Genetic sequencing of an organism's DNA is becoming increasingly important for identifying species. Once you have the morphology and genetic work completed for your specimen, you can look at collections and study what's been published in the scientific literature. Has this type of sand dollar been described already? Does it already have a name? As my study continues, I might realize that no one else has ever seen or described or named this organism before and that is one of the most exciting moments there is for a Taxonomist. By definition it means that I have the opportunity to describe it and name it. And in our science, if you've gone through the hard work to discover that this thing is a new species and deserves a new name, your own name gets associated with that new scientific name. You could be famous, at least, among the small number of people who love sand dollars, any way. The process of building collections is like a rock being dropped in a pool. You get ripples flowing out that can influence all kinds of other areas of biology, now and in the future. With specimens in a collection like our new sand dollar, the information will be there forever, building and adding to our knowledge. We and future generations of scientists can look at evolutionary relationships at diseases and pathologies and who knows what a hundred years from now. Maybe even a way to protect an entire coral reef community will emerge from these studies or new drugs or food sources. Adding that new specimen to the collection creates new ripples, something that's new and interesting and part of the biodiveristy on this planet. It's been documented and preserved forever. Available for study by generations to come. They can take those ripples and directions that we haven't even yet imagined.