Forests of the Past: A Window to Future Changes

Abstract

Forests of theThe following resources related to this article are available online at

The influence of contemporary and historic landscape features on the genetic structure of the sand dune endemic, Cirsium pitcheri (Asteraceae)

“…Although this high divergence may be exacerbated by recent (4150 years) increases in fragmentation because of development in the area, the magnitude of difference is greater than can be expected, given the size of populations and generation time (Lloyd et al, 2013), suggesting that the divergence is in part an historic legacy. The relatively small genetic distance between populations at the southern edge of range to those in Sleeping Bear Dunes National Lakeshore, and given the southern populations only contain a subset of known alleles, would suggest that these populations are the result of sporadic founding events from the range center, rather than the result of a genetic bottleneck at the retreating edge (Hewitt, 2000;Petit et al, 2003Petit et al, , 2008Hu et al, 2009). The presence of two genetic groups in Indiana might suggest separate founding populations, which is not surprising given the dunes in the western portion of Indiana are younger, less stable and wider than those in the east of Indiana (Olson, 1958;Cowles, 1899).…”

“…The distribution of genetic diversity throughout a plant's range is dependent on life-history traits (Hamrick and Godt, 1996;Nybom, 2004), in particular, pollination and dispersal mechanisms (TheilEgenter et al, 2009;Kramer et al, 2011;, available habitat and historical events (Hewitt, 2000;Petit et al, 2003Petit et al, , 2008Hu et al, 2009). Glaciers covered the upper Midwest of North America until 14 000 yBP (Colman et al, 1994b); hence, most of the region's present day vegetation migrated in from unglaciated areas (Gleason, 1922;McLaughlin, 1932).…”

Phylogeographic pattern of range expansion provides evidence for cryptic species lineages in Silene nutans in Western Europe

“…Besides, plant communities are facing strong and fast environmental changes owing to human activities (for example, climate change, habitat fragmentation), threatening their survival in the long term (Hautekèete et al, 2015). Recent studies of the effects of contemporary climate warming on plant species distribution and migration have emphasised the need for a better understanding of species response to past climatic changes (Petit et al, 2008).…”

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“…Knowledge of past forest change serves for a better understanding of the climate system, carbon cycle and genetic diversity, and can inform current predictions and conservation strategies (Prentice et al, 1992;Tarasov et al, 2007;Petit et al, 2008). Botanical records from high-latitude regions of Europe and North America indicate that boreal forests "became established during the Holocene interglacial (the past 11.6 ka) as a result of population invasion from southern glacial refugia and local expansion of small tree populations that survived the Last Glacial Maximum interval (LGM: ~25-17 ka) in cryptic refugia" (Petit et al, 2008).…”

“…Botanical records from high-latitude regions of Europe and North America indicate that boreal forests "became established during the Holocene interglacial (the past 11.6 ka) as a result of population invasion from southern glacial refugia and local expansion of small tree populations that survived the Last Glacial Maximum interval (LGM: ~25-17 ka) in cryptic refugia" (Petit et al, 2008). An extensive dataset of radiocarbon-dated macrofossils from northern Asia provides evidence that boreal trees advanced close to the current arctic coastline between 9 and 7 ka (MacDonald et al, 2000).…”