Cj. Heusser et al., FULL-GLACIAL-LATE-GLACIAL PALEOCLIMATE OF THE SOUTHERN ANDES - EVIDENCE FROM POLLEN, BEETLE AND GLACIAL RECORDS, JQS. Journal of quaternary science, 11(3), 1996, pp. 173-184
Palaeoecological studies carried out in the Chilean Lake District and
Chilotan Archipelago (41 degrees-43 degrees S) record full-glacial and
late-glacial pollen assemblages beginning just after 21000 and beetle
assemblages after 18000, both sets extending until 10000 C-14 yr BP.
Pollen records indicate that Subantarctic Parkland, the vegetation of
the early millennia of record, changed after about 14000 yr BP to beco
me open woodland and later North Patagonian Evergreen Forest. Assembla
ges of plants and beetles, responding more or less in unison to a stro
ng rise in temperature (greater than or equal to 6 degrees C), behaved
in accord at around 14000 until 13000-12500 yr BP, the beetle fauna d
isplaying a marked increase in obligate forest types. During full-glac
ial conditions (17400-16100 and 15300 and 14400 yr BP) and in the late
-glacial interval (after about 13000 yr BP), however, climate evidentl
y coerced populations dissimilarly, the pollen sequence showing an inc
rease in plant taxa indicative of colder climate, whereas the beetle f
auna underwent little or no variation. Contrasting climate modes impli
ed by plants and beetles may be attributed to differential responses t
o apparent low-order temperature changes (less than or equal to 2-3 de
grees C).