Presentation on theme: "Caves A cave is defined as an underground passage large enough for a person to crawl into, naturally formed, and in complete darkness."— Presentation transcript:
1 CavesA cave is defined as an underground passage large enough for a person to crawl into, naturally formed, and in complete darkness.
2 How does a cave form? Rain dissolves Carbon Dioxide into Carbonic acid Carbonic acid dissolves minerals in rockRock is sculpted in weak spotsWater seeps through rocks and makes underground waterwaysWhen the water level drops, the waterway exits the rock through the exiting hole (resurgence)Collections of water creates deep gaps in caves.When the water level outside the cave drops, the cave empties and dries out.
4 Stalactites Stalactites Formed by water that drops from the top of the cave that contains calciteThe calcite is left when the water dropsConstant winds blowing cause stalactites to grow in crooked.Occasionally, stalactites will grow together with the stalagmites and will create a column.
5 Stalagmites Stalagmites: Form from the bottom of the cave They grow about 1 cm every 1000 years because it is hard for water to evaporate in the moist cave
6 Types of StalactitesTypes ofStalactitesIcicle Straw Drape
9 Cave Sections Cave environments fall into three basic categories: Endogean: parts of cave that come into contact with the surfaceExample: cracks, rock seams, groundwater seepage, and root protrusionParahypogean: regions near cave mouths that extend to the last penetration of sunlight.Hypogean: deep in the cave, only come into contact with the surface through wind, underground rivers, or the migration of animals.Considered to be “true” cave environmentsThe deeper the cave becomes, the less biodiversity is found.
10 Types of CavesErosional- formed by the action of water or wind, carrying abrasive particles capable of carving rock
11 Types of CavesLava Tube- lava travels beneath the surface and is expelled by a volcano during an eruption
12 Types of CavesSea Caves- form from wave actions along the coast where areas are weak in sea cliffs
13 Types of CavesSolution Caves- form where rock is dissolved away
14 Cave Organisms Cave organisms fall into three basic classes: Troglobites: “cave dwellers” animals that are specialized for cave life.Can leave for short periods of timeCan complete parts of their life cycles above groundCan’t live entire lives outside of the caveExamples: some bacteria, some flatworms, and blindfish
15 Cave Organisms2. Troglophiles: “cave lovers” can live part or all of their lives in cavesCan complete a life cycle in certain environments on the surfaceExamples: cave crickets, millipedes, pseudoscorpions, and spiders
16 Cave Organisms 3. Trogloxenes: “cave guests” Frequents caves May require caves for a portion of it’s life cycleMust return to the surfaceExamples: Hibernating reptiles and mammals
17 Cave Organisms Troglophobes: “cave haters” Can’t survive in caves for any time periodExample: organisms that fall through sinkholes or frogs swept into caves by flash floods
18 Adaptations of Things that Live in Caves Loss of pigmentLoss of eyesBlue eyes (can absorb light better)Elongation of appendagesEnhancement of other senses (can sense vibrations in water)Echolocation
19 BatsNocturnalThey sleep in the back of caves to keep from being eatenAre found everywhere except Antarctica and the ArticHibernate in cavesWhen weather is warm, the bats leave the caves at night to find foodThey are the only mammals that can flyWings are a membrane of skin that stretches from their body to their fingertips.
20 Horse-shoe BatsHave horseshoe shaped structure around their nostrils to help direct sound for echo locationThey wrap their wings around themselves to keep warm during hibernationWhen they are asleep, they tuck their wings to their sides
21 Bat Communication and Pregnancy Pregnant bats move to a warmer area in the cave to give birthWhen the baby is young, it goes with the mother to get foodWhen it is older, it is left behind and calls to the mother so she can find her way back
22 Where do cave dwellers get food? Some get food from outside the caveSome eat things insideGuano (Bat Poo) falls to the ground where millipedes, beetles, and fungi get their nourishmentDead animalsOrganic debris washes in from streamsCave crayfishCave shrimpFlatworms
23 Cave Studies Speleology- the scientific study of caves. Spelunking- recreational exploring of caves.Cave cartography- creating cave mapsCave geology- study of cave rock.Cave Hydrology- study of water features in caves.