W1: L2 = Methods + Outcomes (Prof. Bamford) Flashcards
Hypotheses proposed regarding Palaeobotany/Palaeoecology? (4)
● The Present is key to the Past.
● Climate has changed (geochemical, sedimentological, faunal evidence).
● Plants are adapted to their immediate environmental conditions.
● Fossil plants will reflect their living environments.
How do fossils plants reflect their living environments? (3)
If climate change is very rapid, plants might respond by:
• Adapting (minor changes or speciation).
• Migrating (shifts).
• Extinction (local only or widespread).
How do fossils plants reflect their living environments? (3)
If climate change is very rapid, plants might respond by:
• Adapting (minor changes or speciation).
• Migrating (shifts).
• Extinction (local only or widespread).
If climate change is very rapid, how might plants respond? (3)
• Adaptation.
• Migration.
• Extinction.
What do we use the Methods of studying fossil plants for studying? (3)
We use these methods for studying:
• Palaeoclimate.
• Biostratigraphy.
• Evolution.
Palaeoclimate attribute?
It has 3 broad approaches namely, taxonomic, physiognomic & biogeochemical.
3 Approaches for Palaeoclimate reconstruction?
• Taxonomic.
• Physiognomic.
• Biogeochemical.
Taxonomic approach?
= uses the Nearest Living Relative (NLR) “rule” or concept.
NLR stands for?
Nearest Living Relative.
NLR criteria/prerequisites needed to use the method? (5)
● Taxonomic identification is required.
● Fossil plants will have the same climatic tolerances as their Nearest living relatives.
● Need good modern databases (SANBI).
● Whole flora must be studied.
● Better for younger floras with living relatives.
Fossils used for the NLR method? (4)
• Leaves.
• Wood.
• Pollen.
• Phytoliths.
NLR method attributes in terms of Palynology? (3)
• Most common for climate & vegetation studies.
• Change in ratio of arboreal:non-arboreal [AP:NAP] (proportion of grass vs trees dominated).
• Zones are based on extinctions/origins or dominance.
Thing to note about the NLR method?
Compare the fossil samples/material with the modern samples/material to help with Palaeoclimate reconstruction.
Explain Regional habitat slide? (2)
• Uses pollen & vegetation to reconstruct the environment.
• Exhibits patterns of change.
Physiognomic approach?
= uses adaptations to infer climatic conditions.
Plant physiognomy attributes? (3)
• Independent of taxonomy.
• Organs are functional.
• Similar physical features are adapted to similar climates.
Organs/Features that Plant physiognomy focus on? (3)
• Leaves.
• Wood.
• Leaf stomatal index.
• Phytoliths.
Leaves functionality?
Functional for efficient photosynthesis in relation to the leaf surface area.
Features that Plant physiognomy considers? (4)
• Leaf area in relation to water loss.
• Leaf area.
• Leaf shape.
• Leaf margins.
Features under Leaf area? (2)
• CO2 uptake.
• Water conservation.
Leaf area in relation to water loss attributes? (2)
• Increased SA, increases photosynthesis BUT also increases water loss.
• Therefore, plants compensate for the water loss in various ways.
How do plants compensate for water loss (Leaf area in relation to water loss)? (5)
• More leaves.
• Smaller leaves.
• Reflective surfaces.
• Stomata below.
• Papillae (hairs).
Leaf area attributes? (4)
• Balance between SA & water retention.
• Large leaves in moist climate.
• Small leaves in cold or dry climate.
• Quantify proportions of certain size classes (calculation).
Leaf area equation?
Leaf area = length × width × ⅔
Some size classes? (3)
• Microphyll.
• Mesophyll.
• Megaphyll.
Leaf shapes use?
Used to infer possible climate that plant is/was found in.
Some Leaf shapes/features? (6)
• Lobed/peltate.
• Small compound.
• Large compound.
• Narrow.
• Drip-tips.
• Elliptic.
What climate does Lobed/peltate leaf shape indicate?
Understorey.
Understorey?
=
What climate does Small compound leaf shape indicate?
Warm.
What climate does large compound leaf shape indicate?
Deciduous.
What climate does narrow leaf shape indicate?
Riparian or disturbed.
What climate does narrow leaf shape indicate?
Riparian or disturbed.
What climate does Drip-tips leaf shape indicate?
Humid.