1. PALEOCLIMATE RECONSTRUCTION: Non-Marine Biologic evidence PALEOCLIMATE RECONSTRUCTION: Non-Marine Biologic evidence (plant macrofossils, treelines, pollen, tree rings) These methods typically reveal information for the These methods typically reveal information for the

2. Tree-line: zone of decreasing tree height with increasing latitude (arctic) or altitude (alpine) Tree-line: zone of decreasing tree height with increasing latitude (arctic) or altitude (alpine)

3. Artic tree-line: corresponds with the Artic tree-line: corresponds with the

4. Evidence of retreating tree lines: north or higher than present tree line found north or higher than present tree-line c. Charcoal layers found north or above present tree line— north or higher than present tree line found north or higher than present tree-line c. Charcoal layers found north or above present tree line—

5. Evidence for advancing tree lines: most evidence comes from Evidence for advancing tree lines: most evidence comes from

6. growth form of trees near the tree line is more complex than arctic tree-line due to orographic rainfall and geomorphic processes like landslides is more complex than arctic tree-line due to orographic rainfall and geomorphic processes like landslides

7. Note fluctuation of arctic tree-line during the last 5000 yr: Note fluctuation of arctic tree-line during the last 5000 yr:

8. Alpine tree-line: studies in Scandanavia and the western US concur that alpine tree-lines during the middle Holocene (~ 5Ka) were ~150 m higher in elevation than today studies in Scandanavia and the western US concur that alpine tree-lines during the middle Holocene (~ 5Ka) were ~150 m higher in elevation than today

9. Evidence from: (genus: Neotoma)—the dens of these animals contain remarkable collections of the Evidence from: (genus: Neotoma)—the dens of these animals contain remarkable collections of the middens in arid climates have been dated back as far as middens in arid climates have been dated back as far as middens indicate that in the SW US 40Ka –12Ka (this corresponds nicely with high stands during the same period—see previous lecture) middens indicate that in the SW US 40Ka –12Ka (this corresponds nicely with high stands during the same period—see previous lecture)

10. middens

11. : a group of insects restricted to specific climate regimes : a group of insects restricted to specific climate regimes One advantage of insects over pollen is that insects respond quickly to climate change; whereas it may take years to change the composition of a forest One advantage of insects over pollen is that insects respond quickly to climate change; whereas it may take years to change the composition of a forest

13. This study from a pond in Maine showed that cold water aquatic insects were common during the Younger Dryas This study from a pond in Maine showed that cold water aquatic insects were common during the Younger Dryas

14. millions of tons of pollen are produced each year creating a constant ‘rain’ of pollen, which is millions of tons of pollen are produced each year creating a constant ‘rain’ of pollen, which is pollen grains are typically 10-150 μm in size and have distinct morphologies pollen grains are typically 10-150 μm in size and have distinct morphologies —those that rely on wind for pollination; these produce the most pollen —those that rely on wind for pollination; these produce the most pollen the method works best for lakes at least 1 km 2 in area—to pick up the

15. Examples Of different Types of Pollen Examples Of different Types of Pollen

18. Studies of pollen from lakes in the Eastern US show that (today this type of forest is found in Canada and higher elevations of the Appalachians) was found on high elevations of the Appalachians (today tundra is restricted to Northern Canada) Studies of pollen from lakes in the Eastern US show that (today this type of forest is found in Canada and higher elevations of the Appalachians) was found on high elevations of the Appalachians (today tundra is restricted to Northern Canada)

20. From BIOGEOGRAPHY, Lomolino et al. p. 295

21. From BIOGEOGRAPHY, Lomolino et al. p. 296