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海 槽 泥 盆 纪 珊 瑚 、 海 百 合 为 华 南 区 。 在 南<br />
秦 岭 褶 皱 带 , 淅 川 陆 棚 寒 武 纪 三 叶 虫 有 华<br />
北 区 和 华 南 区 的 分 子 , 奥 陶 纪 牙 形 石 、 头<br />
中 类 由 华 南 区 变 为 华 北 区 , 晚 奥 陶 世 腕 足<br />
类 、 三 叶 虫 、 珊 瑚 为 华 北 区 , 而 早 志 留 世<br />
笔 石 、 晚 泥 盆 世 珊 瑚 、 腕 足 类 和 蜓 、 古 植<br />
物 以 及 早 石 炭 世 珊 瑚 和 蜓 均 为 华 南 区 ; 南<br />
湾 海 槽 泥 盆 纪 孢 子 为 华 南 区 。 在 此 基 础 上<br />
探 讨 了 东 秦 岭 古 生 代 古 地 理 变 迁 过 程 。<br />
2008010007<br />
个 体 生 态 学 和 生 态 域 的 充 填 : 关 键 后 生 动<br />
物 的 辐 射 = Autecology and The Filling of<br />
Ecospace: Key Metazoan Radiations. ( 英 文 ).<br />
Bambach R K; Bush A M; Erwin D H. Palaeontology,<br />
2007, 50(1): 1-22<br />
All possible combinations of six tiering positions<br />
in relation to the substratum/water interface,<br />
six motility levels and six feeding<br />
strategies define a complete theoretical ecospace<br />
of 216 potential modes of life for marine<br />
animals. The number of modes of life<br />
actually utilized specifies realized ecospace.<br />
Owing to constraints of effectiveness and efficiency<br />
the modern marine fauna utilizes only<br />
about half the potential number of modes of<br />
life, two-thirds of which (62 of 92) are utilized<br />
by animals with readily preserved, mineralized<br />
hard parts. Realized ecospace has increased<br />
markedly since the early evolution of<br />
animal ecosystems. The Ediacaran fauna utilized<br />
at most 12 modes of life, with just two<br />
practised by skeletal organisms. A total of 30<br />
modes of life are recorded in the Early and<br />
Middle Cambrian, 19 of which were utilized<br />
by skeletal organisms. The other 11 are documented<br />
from soft-bodied animals preserved in<br />
the Chengjiang and Burgess Shale Konservat-<br />
Lagerstätten. The number of modes of life<br />
utilized by skeletal organisms increased by<br />
more than 50 per cent during the Ordovician<br />
radiation to a Late Ordovician total of 30. Between<br />
the Late Ordovician and the Recent the<br />
number of utilized modes of life has doubled<br />
again. The autecological and taxonomic diversity<br />
histories of the marine metazoa appear to<br />
be broadly parallel, and future studies of theoretical<br />
ecospace utilization should provide<br />
more detailed tests of pattern and process in<br />
the ecological history of the metazoa.<br />
2008010008<br />
生 命 如 何 变 得 如 此 多 样 依 据 化 石 记 录 和<br />
分 子 系 统 学 得 出 的 多 样 化 的 机 制 = How did<br />
life become so diverse The dynamics of diversification<br />
according to the fossil record and<br />
molecular phylogenetics. ( 英 文 ). Benton M J;<br />
Emerson B C. Palaeontology, 2007, 50(1): 23-<br />
40<br />
The long-term diversification of life probably<br />
cannot be modelled as a simple equilibrial<br />
process: the time scales are too long, the potential<br />
for exploring new ecospace is too large<br />
and it is unlikely that ecological controls can<br />
act at global scales. The sum of many clade<br />
expansions and reductions, each of which<br />
happens according to its own dynamic, probably<br />
approximates more a damped exponential<br />
curve when translated into a global-scale species<br />
diversification curve. Unfortunately, it is<br />
not possible to plot such a meaningful globalscale<br />
species diversification curve through<br />
time, but curves at higher taxonomic levels<br />
have been produced. These curves are subject<br />
to the vagaries of the fossil record, but it is<br />
unlikely that the sources of error entirely<br />
overwhelm the biological signal. Clades radiate<br />
when the external and internal conditions<br />
are right: a new territory or ecospace becomes<br />
available, and the lineage has acquired a number<br />
of characters that open up a new diet or<br />
mode of life. Modern high levels of diversity<br />
in certain speciose clades may depend on such<br />
ancient opportunities taken. Dramatic climatic<br />
changes through the Quaternary must have<br />
driven extinctions and originations, but many<br />
species responded simply by moving to more<br />
favourable locations. Ecological communities<br />
appear to be no more than merely chance associations<br />
of species, but there may be real<br />
interactions among species. Ironically, high<br />
species diversity may lead to more speciation,<br />
not, as had been assumed, less: more species<br />
create more opportunities and selective pressures<br />
for other species to respond to, rather<br />
than capping diversity at a fixed equilibrium<br />
level. Studies from the scale of modern ecosystems<br />
to global long-term patterns in the<br />
fossil record support a model for the exponential<br />
diversification of life, and one explanation<br />
for a pattern of exponential diversification is<br />
that as diversity increases, new forms become<br />
ever more refinements of existing forms. In a<br />
sense the world becomes increasingly divided<br />
into finer niche space. Organisms have a propensity<br />
to speciate freely, species richness<br />
within ecosystems appears to generate opportunities<br />
for more speciation, clades show all<br />
kinds of patterns from sluggish speciation<br />
rates and constant diversity through time to<br />
apparently explosive speciation, and there is<br />
no evidence that rapidly speciating clades<br />
have reached a limit, nor that they are driving<br />
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