Presentation is loading. Please wait.

Presentation is loading. Please wait.

Biodiversity Something catchy here. The outstanding scientific discovery of the twentieth century is not television, or radio, but rather the complexity.

Similar presentations


Presentation on theme: "Biodiversity Something catchy here. The outstanding scientific discovery of the twentieth century is not television, or radio, but rather the complexity."— Presentation transcript:

1 Biodiversity Something catchy here

2 The outstanding scientific discovery of the twentieth century is not television, or radio, but rather the complexity of the land organism. Only those who know the most about it can appreciate how little we know about it. The last word in ignorance is the man who says of an animal or plant: "What good is it?" If the land mechanism as a whole is good, then every part is good, whether we understand it or not. If the biota, in the course of aeons, has built something we like but do not understand, then who but a fool would discard seemingly useless parts? To keep every cog and wheel is the first precaution of intelligent tinkering. Aldo Leopold, A Sand County Almanac, and Sketches Here and There, 1948

3 What is Biodiversity? Biodiversity can be expressed or measured in four different ways: – Genetic variability within a species – Diversity of populations of a species. – Diversity of species within a natural community. – A wide array of natural communities and ecosystems

4 We will focus on diversity of species – Diversity of species within a natural community Examples: – Fish species in a lake – Bird species in a forest – Snail species in a pond or stream – Parasite species in a host

5 So, How Do We Measure Biodiversity? Count species in a pond, river, city, county, state, etc. How many species per unit (e.g., pond, river) How many of each species in an area Richness, abundance, etc Indicator taxa

6 Fort Collins Natural Areas Many cities invest much time and money creating and preserving wildlife habitat The city of Fort Collins manages over 36,000 acres of natural areas in and around the city 37 natural areas (as of early 2008)

7 Great blue heron Animals that use Fort Collins natural areas* Marsupials (1) Insectivores (4) Rabbits and allies (5) Carnivores (14) Even-toed ungulates (3) Bats (8) Rodents (32) Amphibians (6) Snakes (15) Lizards (5) Turtles (3) Fish (32) Birds (297) * Not all animals are found in all natural areas, and some are only occasional or rare visitors Long-tailed weasel, summer coat American bullfrog Western painted turtle Common shiner

8 297 bird species use Fort Collins natural areas! About 75 of these rely on aquatic habitats (streams, ponds, lakes) * Not all birds are found in all natural areas, and some are only occasional or rare visitors

9 How do we figure out if the natural areas provide good bird habitat? Count bird species – Problem: Not all species present all the time Year round residents Migrants (just passing through, but rely on habitat) Seasonal Uncommon Rare

10 Is there another way to figure this out? Find some “surrogate” for measuring bird diversity  PARASITES! Some examples from the literature – Huspeni and Lafferty (2004) Using larval trematodes that parasitize snails to evaluate a saltmarsh restoration project. Ecological Applications 14:795-804 – Hechinger and Lafferty (2005) Host diversity begets parasite diversity: bird final hosts and trematodes in snail intermediate hosts. Proceedings of the Royal Society (B) Biological Sciences 272:1059-1066 – Hechinger et al (2007) Can parasites be indicators of free-living diversity? Relationships between the abundance of larval trematodes and of local benthos and fishes. Oecologia 151:82-92

11 Bird host 2 nd Intermediate host Snail Intermediate host Trematodes, a type of parasitic worm, require two or three hosts to complete their life cycle

12 Wait! I don’t understand! How can we use parasites we find in snails as a “surrogate” for bird diversity? – The parasites we are considering (trematodes) REQUIRE a bird and a snail to complete their life cycle – If the parasite is present in the snail, the bird MUST be present at some point Are there any problems with this method? – Yes…

13 Using trematodes as a surrogate for bird diversity… Problems: – Relationships between trematodes and their snail and bird hosts are not always known – Parasites often difficult to identify to species But there are advantages… – Snails are easy to collect – Snails don’t migrate to other parts of the world, and so are present all year Conclusion: using trematodes as a surrogate for bird diversity appears reasonable…

14 Snails and Trematodes in Larimer County Snail species# of trematode taxa Lymnaea bulimoidesUnknown Lymnaea obrussaUnknown Physa anatinaUnknown Physa ellipticaUnknown Lymnaea elodes7 found Physa integra3 found, including Ribeiroia ondatrae Gyraulus parvus6 found Helisoma trivolvis55 found! Including Ribeiroia ondatrae The number of any species that we know about depends on the amount of research that has been done People are interested in Ribeiroia ondatrae because it causes frog deformities Helisoma trivolvis is well- studied because it is a common host for Ribeiroia ondatrae, and because it is common in some areas * These numbers come from research across the United States, not just Colorado

15 The Activity It would be great to use real snails and real trematodes for this activity… That would require specialized training in parasitology, and many hours out in the field Instead, we will use plastic eggs and jelly beans as surrogates for snails and trematodes The idea and the statistics are exactly the same as they would be if we were to use real snails and real trematodes, but it is less messy and a whole lot easier!

16 The Activity Everybody will receive one plastic egg Each egg will contain variable numbers and colors of jelly beans The eggs represent snails The jelly beans represent trematodes, but it’s okay to eat them when you’re done

17 In Class Fill out the ‘species’ information forms in class Hand in your forms before you leave A tally of the ‘species’ will be posted on RamCT – these are the numbers you will use in your analyses

18 Outside of Class Collaborate with a partner to calculate measures of biodiversity using the equations provided on the handout After completing your calculations, follow the instructions on the module website to complete your written report

19 Equations Species richness = S = total number of species Abundance = total # trematodes / total # snails = total # jelly beans / total # plastic eggs Evenness = J’ = variability in species abundances


Download ppt "Biodiversity Something catchy here. The outstanding scientific discovery of the twentieth century is not television, or radio, but rather the complexity."

Similar presentations


Ads by Google