genomes to ecosystems lecture 8- migrations

Question 1

what are advantages to mutations?

Answer 1

-exploit new resources seasonally
-protection of vulnerable
-avoiding inbreeding during depression
-reduces competition

Question 2

what are the risks of migration?

Answer 2

-bad weather
-lack of emergency stops
-predation
-disorientation
-potential lack of final stops

Question 3

what the methodology to track migration?

Answer 3

-point counts
-natural markings
-radar
-statellite tracking

Question 4

what does biomechanics aid in birds?

Answer 4

birds have different wing shapes and sizes.

Elliptical wings tend to be found on birds adapted to forested, wooded and shrubby habitats where birds require good maneuverability and are generally short with a low aspect ratio. These wings often have a high degree of slotting which is associated with the requirement of slow speed flight.

High speed wings are possessed by birds that feed in the air or have to make long migratory hauls. They are seen in the swifts, swallows and also the falcons and some shorebirds. These wings have a relatively high aspect ratio and are only slightly cambered, having an almost flat profile and are often swept back.

Question 5

how do migrating birds have a different fatty acid contribution to energy?

Answer 5

its highly accessible and easy to molibise fuel source

Question 6

how else have godwits changed their body composition?

Answer 6

increased muscle tissue, lungs and heart and decreased stomach, kidney and liver

Question 7

what migration physiology adaptations do animals have?

Answer 7

Energetic adaptations:
Biomechanical ‘shape’ reduce costs of transport
Internal physiological changes to increase flight performance ‘equipment’ and increase fuel reserves
birds also eat excessively to prepare for the migration and double in body mass

Question 8

what effects do humans have?

Answer 8

Easy overexploitation by humans
Passenger pigeon exploitation.
Historic whale harvesting
Sea turtle exploitation?
Bison: killed for fur and leather

Effects of light altering orientation cues– Influence of artificial light on nocturnal migrants
Lots of small birds migrate at night to avoid predation
Sea turtles emerge at night to avoid predation. Need to head to water ASAP, use moon for orientation. BUT shore-front lighting confuses them- lead them away from water