منابع مشابه
Why are there so many explanations for primate brain evolution?
The question as to why primates have evolved unusually large brains has received much attention, with many alternative proposals all supported by evidence. We review the main hypotheses, the assumptions they make and the evidence for and against them. Taking as our starting point the fact that every hypothesis has sound empirical evidence to support it, we argue that the hypotheses are best int...
متن کاملWhy Are There So Many N = 4 Superstrings ?
We demonstrate the existence of three off-shell distinct N = 4 super-strings at the level of manifest locally supersymmetric Lagrangian field theories on the world sheet.
متن کاملWhy are there so many species in the tropics?
Known for centuries, the geographical pattern of increasing biodiversity from the poles to the equator is one of the most pervasive features of life on Earth. A longstanding goal of biogeographers has been to understand the primary factors that generate and maintain high diversity in the tropics. Many 'historical' and 'ecological' hypotheses have been proposed and debated, but there is still li...
متن کاملWhy are there so few smart mammals (but so many smart birds)?
The expensive brain hypothesis predicts an interspecific link between relative brain size and life-history pace. Indeed, animals with relatively large brains have reduced rates of growth and reproduction. However, they also have increased total lifespan. Here we show that the reduction in production with increasing brain size is not fully compensated by the increase in lifespan. Consequently, t...
متن کاملWhy are so many trees hollow?
In many living trees, much of the interior of the trunk can be rotten or even hollowed out. Previously, this has been suggested to be adaptive, with microbial or animal consumption of interior wood producing a rain of nutrients to the soil beneath the tree that allows recycling of those nutrients into new growth via the trees roots. Here I propose an alternative (non-exclusive) explanation: suc...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Contexts
سال: 2004
ISSN: 1536-5042,1537-6052
DOI: 10.1525/ctx.2004.3.1.38