3. Adaptations of Animals to High Elevation Flashcards
Typical alpine environmental conditions from an animal perspective:
- Temperature – cold or hot, rapid changes, precipitation as snow all year
- Windy
- Long winters
- Steep and unstable slopes
- Generally low water and food availability
- Low oxygen – depends on elevation
Mountain Goats
- These incredible climbers are found in several of the large mountain ranges in north America
- Usually find them at the top third of the mountain living at the peaks and sheer rock faces.
- They live in family groups which helps them avoid predators thick insulated fur to keep them warm
- Body is large with short appendages to help with heat loss
- Very muscular legs to help run up steep cliffs
- Most notably, their Signature adaptation to deal with steep terrain is their feet
What adaptations do Mountain Goats have?
Specialized hooves
- Textured, rubbery pads that provide traction
- Cloven hooves that can spread apart and move independently
- Back of their feet have sharp dewclaws that keep them from slipping
Bighorn Sheep
- Another example of a well adapted mountain species similar to the mountain goat is the bighorn sheep
- These sheep are also found in various mountain ranges across north America however this species lives a little lower down on the mountain
- So they share many of the same adaptation as the mountain goat but a little less extreme
- They also live in groups for safety,
- They have thick fur, and are very agile on steep terrain
What adaptations do Bighorn Sheep have?
- Just like the mountain goat, they too have specially adapted hooves that allow them to stick to the side of the cliffs
- This is important because they need to be able not just to get around but also avoid predators
- They have their babies near the peaks of the mountains in the spring to keep them away from predators and once they babies get a little
- Older they start to come down, but even the babies are incredibly agile on the cliffs.
Alpine Ibex
Found in the European Alps
Summary of adaptations for mountain goats and bighorn sheep
- Specially adapted hooves – separated into halves
- Thick layer of coarse hair over their usual coat in the winter
- Familiarity with steep terrain and their territories
- Acute eyesight (~2 Km)
- Run at high speeds even on cliff faces (>30 Km/h)
- Travel in family groups to reduce risk of predation
- Specialized digestion allows them to get the most out of a poor diet:
Complex four compartment stomach allows them to obtain nutrients from forage
Eat a lot of forage rapidly and then retreat to a safe cliff to digest away from predators
Large teeth that grow throughout their life allows for grinding coarse grasses and grit
Wild Yaks
- Live high in the Himalayan mountains ~5500 m above sea level
- Have developed large lungs and a large heart to deal with low oxygen at altitude
- Thick fur coat, large body, short appendages, and specialized hooves etc.
-They are so well equipped to deal with the mountains and the elevation that people who live in the Himalayas have domesticated them and use them for transporting good and for food and milk
Strategies to cope with the cold
- Avoid the cold (Don’t let it get you!)
- Migrate
- Insulate: Burrows, Hair, Fat, Size, Physiology
- Deal with it (let yourself get cold!)
-Freeze
-Hibernate
Migrating across latitudes
- Alpine Swift
- Migrate south to avoid harsh conditions imposed by winter in the mountains
- Migrate distances of ~2000 km without stopping
- They forage and sleep while in flight
- This trip can take up to 6 months
Migrate across elevations
- Altitudinal bird migration involves annual seasonal movements up and down elevational gradients
- Of species wintering within USA & Canada ~30% engage in altitudinal migrations
- Higher elevation to lower elevation and back
- Several mammalian species also migrate across elevations
- This increasing their ability to find food and stay warm away from the extreme conditions on the mountain
Insulation
The other strategy for avoiding the cold is insulating
The umbrella term for many different behavioral strategies and physiological responses
Thermoregulation
Ability of the body to maintain its core internal temperature
Types of thermoregulation
- Physiological Mechanisms
- Neural responses (immediate): e.g. modification of blood flow to skin, sweating, shivering etc.
Acclimation responses (long-term): Changes in insulation, increased capacity for metabolic heat generation etc. - Behavioural Mechanisms
- Controlling body temperature by repositioning the body in the environment
Thermoregulation: Body temperature falls
Body vessels constrict so that heat is conserved. Sweat glands do not secret fluid. Shivering (involuntary contraction of muscles) generates heat, which warms the body
- Heat is retained
