Genetic diversity Flashcards
How was initial genetic diversity selected for
selection based on
size
temerment
carcass quality
milk prodcution
disease resistance
wool type
colour
has selection changed
selection ahs changed dramatically from the ancestor that was first domesticated
what is the genetic drift and what two things did it cause
changes in allele frequencies due to chance events
caused:
founder effect
bottleneck effect
causes minor allele frequencie and fixation of major allele = loss in genetic diversity
what is the founder effect
a new coloney is established when a few individuals leave on their own
what is the bottleneck effect
reduction or prevention of reproduction
see different diversity depending on who survives
wide vs tight bottleneck
why did the bison population bottleneck
introduction of horses = increased hunting rates
potentially cattle diseases
european hide demand
railroad development
leather belt = industrial revolution
how has genetic diversity been declining
less variability
less options to respond - economic opportunities, environment issues, food security and biosecurity
world population has increases but genetic diversity has decreases
what happened during the irish potatoe famine
potatoes were introduced to europe in 1530
small number of potatoes introduced to ireland - bottleneck
disease caused by fungus phytophthora infestans
lost more than half of annual potatoe crops from 1845-1852
1 mill died 1 mill fled
why the decline in livestock genetic diversity?
farming is a business : economics and uniformity
use of a few superior animals: modern transportation, AI ET, cloning
when was cattle domesticated
taurine cattle domesticated from aurochs
10 000 years ago in the near east
sporatic interbreeding until the middle ages
aurochs went extinct in poland in 1627
what are heck cattle
developed by the heck brothers
intertwined with nazi germany
attempted to back breed modern cattle to resemble the aurochs
currently 2000 in europe
what is the taurus project
german project
attempting to improve heck cattle for re wilding purposes
1997
heck, sayaguesa chainina toro de lidia
tauros programme
durch project
attempting to backbreed from scratch
2008
auerrind project
2013
natural grazing, back breeding scientific research on aurochs
2018 : signed agreement with the tauros programme
foundational breeds: chianina, sayageusa, maremmana, hungarian grey and watusi
why use conservation?
keep potential useful genes
overcome selection plateaus
heterosis
insurance policies
food security
