host-shifts

Question 1

range of most parasite-host and insect-plant herbivores

Answer 1

narrow (local adaptation)

Question 2

Evolution of host range is linked to

Answer 2

host adaptation

Question 3

Examples of pathogenic host shifts

Answer 3

Dutch Elm disease

chytrid

Covid-19

Question 4

Zoonoses

Answer 4

infections of humans by pathogens from non-humans

Question 5

Host relatedness may affect

Answer 5

a pathogen’s ability to host shift
- parasite infection declines with genetic distance from natural host
- success varies between different host clades

Question 6

Phylogenetic distance

Answer 6

Indicative of local “host” adaptation

Question 7

Naïve” hosts

Question 8

Ecological fitting

Answer 8

process whereby organisms colonize and persist in novel environments, use
novel resources or form novel associations with other species

• Resource-tracking vs. phenotypic plasticity

Question 9

Proposed mechanisms of ecological fitting:

Answer 9

• phenotypic plasticity
• correlated trait evolution
• phylogenetic conservatism of environmental niches

Question 10

why are not all hosts/pathogens in population available for host shift

Answer 10

• phenotypic plasticity
• correlated trait evolution
• phylogenetic conservatism of environmental niches

Question 11

Pathogen-host coevolution

Answer 11

1) Often governed by host-shift speciation
2) Pathogen-host adaptation
3) Niche-differentiation
4) Trade-off between specializing on one
resource and the capacity to use other
resources

Question 12

Inter-specific diversity in Metarhizium

Answer 12

specialist (growth strategy)
generalist (toxin strategy)

All isolates are virulent towards both locust species
- variable virulence towards beetles

Question 13

Studying host shifts with

Answer 13

serial passaging