CavesCaves

A A cavecave is defined as an underground is defined as an underground passage large enough for a person to passage large enough for a person to

crawl into, naturally formed, and in crawl into, naturally formed, and in complete darkness.complete darkness.

How does a cave form?How does a cave form?1. Rain dissolves Carbon Dioxide into Carbonic acid2. Carbonic acid dissolves minerals in rock3. Rock is sculpted in weak spots4. Water seeps through rocks and makes underground

waterways5. When the water level drops, the waterway exits the

rock through the exiting hole (resurgence)6. Collections of water creates deep gaps in caves.7. When the water level outside the cave drops, the cave

empties and dries out.

StalactitesStalactites

• Stalactites– Formed by water that

drops from the top of the cave that contains calcite

– The calcite is left when the water drops

– Constant winds blowing cause stalactites to grow in crooked.

– Occasionally, stalactites will grow together with the stalagmites and will create a column.

StalagmitesStalagmites

• 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

Types of StalactitesTypes of Stalactites

• Types of Stalactites

• Icicle Straw Drape

Types of StalagmitesTypes of Stalagmites

• Dish Stack Fir Cone

OthersOthers

Cave SectionsCave Sections• Cave environments fall into three basic categories:1. Endogean: parts of cave that come into contact with

the surface– Example: cracks, rock seams, groundwater seepage, and root

protrusion2. Parahypogean: regions near cave mouths that extend

to the last penetration of sunlight.3. 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 environments• The deeper the cave becomes, the less biodiversity is

found.

Types of CavesTypes of Caves

• Erosional- formed by the action of water or wind, carrying abrasive particles capable of carving rock

Types of CavesTypes of Caves

• Lava Tube- lava travels beneath the surface and is expelled by a volcano during an eruption

Types of CavesTypes of Caves

• Sea Caves- form from wave actions along the coast where areas are weak in sea cliffs

Types of CavesTypes of Caves

• Solution Caves- form where rock is dissolved away

Cave OrganismsCave Organisms• Cave organisms fall into three basic

classes:1. Troglobites: “cave dwellers” animals that are

specialized for cave life.– Can leave for short periods of time– Can complete parts of their life cycles above ground– Can’t live entire lives outside of the cave– Examples: some bacteria, some flatworms, and

blindfish

Cave OrganismsCave Organisms2. Troglophiles: “cave lovers” can live

part or all of their lives in caves– Can complete a life cycle in certain

environments on the surface– Examples: cave crickets, millipedes,

pseudoscorpions, and spiders

Cave OrganismsCave Organisms

3. Trogloxenes: “cave guests”– Frequents caves– May require caves for a portion of it’s life

cycle– Must return to the surface– Examples: Hibernating reptiles and

mammals

Cave OrganismsCave Organisms

• Troglophobes: “cave haters”• Can’t survive in caves for any time period• Example: organisms that fall through

sinkholes or frogs swept into caves by flash floods

Adaptations of Things that Live in Adaptations of Things that Live in CavesCaves

• Loss of pigment• Loss of eyes• Blue eyes (can absorb light better)• Elongation of appendages• Enhancement of other senses (can sense

vibrations in water)• Echolocation

BatsBats• Nocturnal• They sleep in the back of caves to keep from

being eaten• Are found everywhere except Antarctica and the

Artic• Hibernate in caves• When weather is warm, the bats leave the caves

at night to find food• They are the only mammals that can fly• Wings are a membrane of skin that stretches

from their body to their fingertips.

Horse-shoe BatsHorse-shoe Bats

• Have horseshoe shaped structure around their nostrils to help direct sound for echo location

• They wrap their wings around themselves to keep warm during hibernation

• When they are asleep, they tuck their wings to their sides

Bat Communication and PregnancyBat Communication and Pregnancy

• Pregnant bats move to a warmer area in the cave to give birth

• When the baby is young, it goes with the mother to get food

• When it is older, it is left behind and calls to the mother so she can find her way back

Where do cave dwellers get food?Where do cave dwellers get food?

• Some get food from outside the cave• Some eat things inside

– Guano (Bat Poo) falls to the ground where millipedes, beetles, and fungi get their nourishment

– Dead animals– Organic debris washes in from streams– Cave crayfish– Cave shrimp– Flatworms

Cave StudiesCave Studies

• Speleology- the scientific study of caves.• Spelunking- recreational exploring of

caves.• Cave cartography- creating cave maps• Cave geology- study of cave rock.• Cave Hydrology- study of water features

in caves.

Endangered SpeciesEndangered Species

• Tooth cave spider

Endangered SpeciesEndangered Species

• Trapdoor spider

Endangered SpeciesEndangered Species

• Gray Bat