Species Level Impacts Of CC

Question 1

What are the 6 types of response a species could do

Answer 1

1. Behavioural
2. Adaptive micro evolution
3. Adaptive macro evolution
4. Changes in geographical distribution
5. Abundance changes
6. Extinction

Wrong order

Question 2

How much of the earths surface will have novel climates by 2100 with about 2 degree warming

Answer 2

20%

Question 3

Thermophilisation

Answer 3

thermal migration (degree per year)

Thermophilisation of communities mainly driven by cold adapted spp mortality. Change in community composition- non analog.

Question 4

Liana

Answer 4

Incr in liana in long term monitored plots in tropical rainforests eg amazon

abundance assoicated with low tree biomass. They put lots of leaves into canopy–> shade.

Thought to benefit from increased CO2 more so than trees. Proportionally greater leaf area –> greater C fixation channeled into growth than trees.

BUT experimental evidence suggests that temp is the influencing factor –> needs to be tested. lianas aren’t growing THAT much more than trees are therefore not co2

Question 5

Spp level impacts

Behavioural

Answer 5

Include phenological shifts. No genetic adaptive component. Rapid, can be elicited even by seasonal climatic patterns or intra annual variability. Issues discussing this with cc that there are huge differences year on year

Question 6

Spp level impacts

Adaptive microevolution

Answer 6

Predominant response to relatively slow to moderate rate of change at moderate magnitude. Results from selection amongst pre-existing genotypes

• variability generate by recombination of alleles resulting from sexual reproduction and crossing over of chromosomes during meiosis
• relatively rapid- not dependent on favourable new mutations
• limited in scope by pre-existing genetic variability

Selecting for what we already have

Question 7

Spp level impacts

Adaptive macro- evolution

Answer 7

Elicited by relatively slow and especially larger magnitude changes. Depends upon chance acquisition of mutations favoured by new condition. Underlies evolution of major lineages over geological time scales eg forestation –> mammoths couldn’t survive

Question 8

Spp level impacts

Changes in relative abundance

Answer 8

Rapid changes, small magnitude. Results from sensitivity of species key life-cycle stages to the environment. Changes not only in composition of communities but also the structural attributes of ecosystem. Lots of what we see now with CC in last few decades.

Question 9

Spp level impacts

Spatial responses

Answer 9

Predominant response

Especially changes of relatively large magnitude occurring relatively rapidly. Linked to spp dispersal capabilities. rate at which spp can extend geographical distribution into newly suitable areas or its ability to colonise such areas when they are isolated from its current range, largely determined by diserpsal.

Question 10

Spp level impacts

Extinction

Answer 10

Species unable to disperse rapidly enough or over such long distances, and or unable to evolve suitable enough adaptations to new conditions. Condition to which they are adapted for no longer available. Spp most at risk: spatially limited environments, small pops, long lifetimes, low reproductive output, relatively sedentary, prey not moving

Question 11

Phenology

Answer 11

Timing of key events in organisms life cycle

Events usually triggered through mechanisms sensitive to day length or to seasonal climate- most often seasonal temps. Changes can affect organisms that rely on home. have record of eg daffodils way back so can see how they’ve changes

Question 12

Phenocam

Answer 12

Can get shots across landscape about what’s happening daily, eg leaf colour, bud burst, can also link it up with CO2

Also get satellite access to assess greenness. Can see changes over the year. Good way of remotely getting data

Earth Observation data, time series of data provide a way to monitor global phenology in terms of greening

Multiyear data sets provide a basis for analysing the relationships between global and phenological patterns and climate. These data also highlight the phenology of the seasonal tropics where moisture availability, rather than temp, controls the pattern of greening (the ‘hydro period’)

Question 13

Photoperiodic triggering

Answer 13

Higher plants- flowering. Both long day (respond to incr day length) and short day flowering responses
- leaf abscission

Animals- short day responses- insects enter diapause

• migratory bird changes
• long day reponses- insects break diapause, inception of antler growth

Question 14

Seasonal climatic triggering and garden experiments

Answer 14

78 sites across europe established in 1957.
Series of clonal vegetatively propagated plant taxa grown in each garden, so phenological differences aren’t due to genetics. One or more annual phenological events recorded from each taxon in garden. Cover range of longitude and latitude.

Individually maintained records also valuable- eg Gilbert White ‘natures calendar’ citizen science

Mechanisms of triggering rarely known. Most info we have if from observation of interannual event timing and climate

Question 15

evidence of timing changes

Answer 15

in Eu many plants have been flowering and leaf unfolding 1.4-3.1 days per decade earlier (over last 30-48 years)

18 butterfly spp in UK, 2.8-3.2 dvd earlier appearance (23 yrs)

Numerous bird spp, Eu and N USA, earlier spring migration 1.3-4.4 did earlier and breeding 1.9-4.8 did earlier (30-60 yrs)

Over long periods this data has been collected so not just inter annual variability

Question 16

Evidence of phenological responses for 677 spp

Answer 16

Parmesan and Yohe 2003

Phenological records for 677 spp over a time period of 16-132 years.

62% showed advancement in date of spring phenological events

Overall mean trend about 3dpd advance

Differences between major taxonomic groups

• mammals about 10 dpd
• amphibians 8dpd
• herbaceous plants 1dpd
• shrubs 1 dpd

Northern hemisphere first leaf data also earlier Comparison of phenological and temp date indicate strong correlation. Given large number of spp responses
–> causal (v likely)

Decades worn change genotypes not long enough. particularly perennial plants that live for ages

Question 17

Mismatching example

Answer 17

Spp A responds to photoperiod
Spp B responds to accumulated warmth

B feeds on A and its phenology was optimised to synchronise its emergence when A was most abundant/palatable/nutritious

following warming, B emerges too early and suffers food shortage - may delay development and incr exposure to predation

Question 18

Growing degree days

Answer 18

Accumulated warmth

At day 0 is threshold day

If we know a plant strats growing at 5 degrees we take every days temp and all days over 5 degrees we take difference (10-5=5) Then sum

Thats the thermal sum when plants start to grow

Question 19

Budburst of oak and moth hatching

Answer 19

Vissec and holleman 2001

incr asynchrony between bud burst of Pedunculate oak and egg hatching in winter moth

Synchronisation ensures larvae fed on newly expanding oak leaves. they are soft, highly nutritious, palatable (tannins and other phenolics that protect mature foliage haven’t accumulated yet)

There s been a series of warm winters since 1975 where egg hatching and bud burst were near synchronous in 80s, but by 99 the eggs were hatching about 20 days too early.

Newly hatched larvae survive about 2-3 days without food (max 10).

Asynchrony= deaths of large proportion of larvae

many small birds that eat the larvae- important for their young- effected too

Question 20

Earlier spring greening consequences

Answer 20

If leaf fall is not advanced or even delayed, ought to have increased photosynthetic uptake and hence slow the rate of atmospheric co2 conc … if warmer winters do not compensate by increased respiration rates

during 70s and 80s seasonal amplitude of the Mauna Loa Co2 curve incr indicating both phot and respiration rates increased

Recent work has shown enhanced summer phot was principally in N uSA, enhanced winter resp principally in eurasia. Amplitude declined in 90s related to the effect of summer droughts on photosynthesis in N uSA

Then increase sharply after a return to more typical rainfall in 2004 - signal is confounded by changes in predominant circulation patterns. Reduced transport of air masses from eurasia to n hemisphere also contributed to reduction in amplitude seen in 90s.

Question 21

Budburst in Fennoscandia

Answer 21

Bennie et al (2010)

Betula pubescens (downy birch) in Fennoscandia. They successfully modelled bud burst in relation to spring temps and frost incidence. But relationship varies systematically across spp ranges with a small heat sum needed for bb. Degree days changing in system

Question 22

Black cap and plastic adaptation

Answer 22

Sylvia atriacapilla

Breeds widely throughout europe and exhibits a variety of migratory behaviours. Some populations migrate to subsaharan Africa for the n.b seasons, some only to iberian peninsula, or other to Eu, North Africa.

More recently numbers of some central eu pops that typically migrated SW to iberian peninsula are migrating W/NW and spending nb season in british isles

Plastic adaptation

Occasional overwintering from 50s onwards; ringing showed where they were from.

1965 some members of central EU pop regularly migrated to spend nb here. 1000-1500km north of other wintering areas around mediteranean. Berthold et al (1992) showed this to be an inherited trait

10% of breeding populations in Germany and Australia now migrate to british isles

Question 23

Fossil record

Answer 23

As yet, ancient DNA records limited to non-coding regions so tells us nothing about potentially adaptive changes. Principally have evidence of morphological adaptation to quaternary climatic cycles- few examples

Bushytailed woodrat one

Question 24

Bushy tailed woodrat

Answer 24

Neotama cinerea

Found across a range of latitudes in western north america. Exhibits a body size cline with latitude. Individuals north on average larger than those in south (Bergmans rule)

Body mass can be estimated from fossil remains

• series of fossil in central current range measured and C14 dated
• body mass greater than today during last glacial and showed a minimum corresponding to independently inferred maximum regional temps during early holocene
• inferred to an adaptive response to CC and probably a genetic determined response
• range of inferred body mass fall within range observed at present day along cline–> adaptive response limited by spp inherent genetic variability

Question 25

Snail

Answer 25

Pupilla muscorum

Small snarled that exhibits a marked W-E cline in shell morphology across its Eu range. Shells from deposits in france representing full glacial, interglacial, and interstadial intervals examined

Interglacial shells match morphology of modern shells from France

Glacial morphology closest to modern shells near the spp present eastern range limit in Poland

Interstadial intermediate in form, closest to morphology from near the longitudinal centre of spp range

Likely shell morphology genetically determined range of forms once again encompassed by spp present variability

Indirect? but fits nicely with thesis that things change in response to climate

Question 26

Adaptive vs spatial response

Answer 26

Observed adaptive genetic responses are the local expression of the spatial response. Possible that most species could not realise such adaptive responses without also a spatial response
- breadth of response in rat and snail probably made it possible only by movement of the spp range and of populations across that range and in response to climatic changes

pic on phone

Weight of evidence suggests adaptive genetic responses were a secondary response to quaternary climatic functions

• no examples to suggest a dominant evolutionary response
• Bennett (90,97) agued that the relatively rapid Quaternary climatic fluctuations led to frequency reversals in selective pressures with the result that, at least for higher organisms, evolving to adapt to these fluctuations is a viable option
• rapid fluctuations may have selected fro the ability to achieve rapid spatial responses –> perhaps also for rapid gene flow through spp that would facilitate local adaptive responses

(little genetic evidence from fossil evidence)