from Tribes to Empires

6.0 Introduction

Homo sapiens sapiens is characterized by several attributes that were needed together for the attainment of an evolutive level superior to that of other primates. The chances for the phylum of the chordates to fulfil its potentialities and reach human … Continue reading

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6.1 Individualization of the human organism

The cornerstones of the sense of individuality and uniqueness that pervade the members of the human species are its immune, hormonal and nervous systems. These systems are deeply rooted in the chordate phylum and developed along other lines in other … Continue reading

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6.2 Biological intelligence and survival

Some organisms endowed with a low degree of consciousness succeeded in living during millions of years without change. For example the species of horseshoe crab that lives on the Florida Gulf coast (see fig. 5.14) is 500 million years old. … Continue reading

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6.3 Levels of encephalization of the vertebrates

Learning, with its corollary, memory, is the incorporation of individual experience into adaptive responses to challenges of the environment. They both represent an important evolutionary step, which allowed animals to adapt to environmental conditions not anticipated by the genetic code, … Continue reading

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6.4 From biological intelligence to human intelligence

6.4.1 Emission and perception of signals Organisms ranging from microbes to mammals make use of chemicals to find mates, recruit symbionts, deter enemies, and fend off pathogens. Our own human reliance on visual and acoustic signals notwithstanding, it is by … Continue reading

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6.5 Human cognitive development

What makes humans special as a species? How do we differ from other species? According to Tomasello 8, primates differ from all other mammals in possessing a greater understanding of relational categories in the social domains. For their part, Hominids … Continue reading

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6.6 Conclusion

To be or not to be is fundamental for atoms and molecules. Isotopes, isomers and enantiomorphs allow for a certain variability but, in general, a small change in an atomic or molecular structure provokes a radical and absolute change in … Continue reading

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7.0 Introduction

The geneticist Theodosius Dobzhansky published in 19371 his concept about the origin of Species. The views of the ornithologist Ernst Mayr followed in 19422. The paleontologist George Sympson contributed his own ideas3. These three views were synthesized into the concept … Continue reading

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7.1 The first hominids

The extensive ice deposits that began to appear six million years ago on the poles lowered substantially the level of the seas, dried up part of the earth and erased plant life in many regions. When the ice melted, the … Continue reading

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7.2 The Australopithecines

Abundant remains of 5 different species of Australopithecines are found in Pliocene rocks all over East Africa, from Lesotho to Ethiopia. They are about 4.3 to 2.5 million years old. Remains of an Australopithecine species found at Hadar in Ethiopia … Continue reading

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