Evolutionary Microbiology

Chapter 12. Human – Apex of All Life?

Jong-Soon Choi

Chungnam National Univ. GRAST

University of Science and Technology

Korea Basic Science Institute

247

Human vs. Human Being

Human - a person as distinguished from

an animal or an alien.

Human Being – a man, woman or child of

the species Homo sapiens, distinguished

from other animals.

What is human being superior to other

animals? - mental development, power of

articulate speech, and upright stance

Man vs Woman – ‘man’ was originally

gender neutral, meaning “person”. ‘man’

started to refer to ‘male human’; ‘woman’

was referred to as ‘wif’ or ‘wifmann,

meaning ‘female human’, ‘wif’ changed to

‘wife’ GENDER EQUITY

(Source: www.google.com) 248

Humans as a species

Human as taxonomy – Homo sapiens sapiens,

extinct species of humans: Neanderthals, Denisovans, Hominid

Human nature – a virtue associated with

basic ethics of altruism derived from the

human condition: love, kindness, social

intelligence

Human condition – defined as the

characteristics, key events, and situations to

compose the essentials of human existence:

religion, philosophy, history, art & literature,

sociology, psychology and human biology

(Source: Wikipedia) 249

Human Chronicle

13.5 BYA Matter and Energy from Big Bang

4.5 BYA Earth planet formed

3.8 BYA Primitive life occurred

6 MYA Ancestor of human & monkey

2.5 MYA Genus Homo in Africa

2 MYA Various human sp. Evolved

500 KYA Neanderthals in Europe and ME

300 KYA “Catch Fire”

200 KYA Homo sapiens in East Africa

70 KYA <Cognition Revolution> in Human

12 KYA <Agricultural Revolution>

5 KYA Language w/letter, written history

500 YA Scientific Renaissance

200 YA <Industrial Revolution>

(Source: www.google.com) 250

Cognition Revolution in Human History

First Human Drawing?

Chauvet-Pont d’Arc drawings, Southern France, 30 KYA

Egyptian pyramids 4.6 KYA

Pyramids at Giza showing three

largest pyramid of Menkaure, Khafre,

Khufu

(Source: www.google.com)

251

Homo

Homo is the genus consisting the

species of Homo sapiens (modern

humans) as well as several extinct

species.

Homo was 2.8 MYA as its earliest

species Homo habilis emerging from

the genus Australopithecus which

was split from the lineage of the

genus Pan, the chimpanzees.Evolutionary tree chart describing

The subfamily Homininae and the

Tribe Homini

A. africanus

(Source: www.google.com)

252

Human Evolution

A model of the evolution of the

genus Homo over the last 2 MYA

- Out of Africa : 1.2 MYA

- Neanderthals : 300 KYA

- Modern sapiens : 250 KYA

SpeciesTempral

rangeHabitat

Adult

Height

H. habilis2.1-1.5

MYAAfrica 150 cm

H. erectus1.9-0.07

MYA

Africa

Eurasia180 cm

H. antecessor1.2-0.8

MYASpain 175 cm

H. heidelbergensis600-350

KYA

Europe

Africa

China

180 cm

H.

neanderthalensis

350-40

KYA

Europe

West Asia170 cm

H. floresiensis100-12

KYAIndonesia 100 cm

Denisova

homini40 KYA Russia ?

H. sapiens 200 KYA Worldwide150~190

cm

Comparison of modern & extinct humans

(Source: Wikipedia)

253

Rise of Homo sapiens

World map of early human

migrations according to

mitochondrial population genetics

KYA

15만년 전 (Africa)

5만년 전 (Europe)

7만년 전(South Asia)

6만년 전(Australia)

3.5만년 전 (Far East)

1.5만년 전 (N. America)

1.2만년 전 (S. America)

(Source: www.google.com) 254

Occupation of Earth by Homo sapiens

Map showing human population density across the globe.

The Earth as seen at

night from space in

October 2000, showing

the extent of human

occupation of the planet.

(Source: www.google.com) 255

Traits of Homo sapiens

Bipedalism : adaptation of terrestrial

locomotion by two rear limbs, leaving frontal

limbs (hands) free : bipedalism raises the

head to allow a greater field of vision

Encephalization : the amount of brain mass

related to an animal’s total body mass :

volumes of brain in 60 kg-other mammal (200

cm3), hominid 2.5MYA (600 cm2), modern

human (1300 cm2)

Sexual dimorphism : the condition where the

two sexes of the same species exhibit

different characteristics beyond the

differences in their sexual organs themselves

(Source: www.google.com) 256

Scrambled Neanderthal Genome into H. sapiens

Between 2% and 4% of the genome of

Europeans and Asians is believed to be

a legacy of interbreeding between

ancient Homo sapiens and Neanderthals.Massacre by

smarter H. sapiens?

(Source: www.google.com)

257

Cooking Up Bigger Brains

Cooking food helped early

humans grow bigger brains

We would need to eat raw

food for 9 hours without rest

in order to get the same

energy kick.

Cooking meat changes

shorter intestines,

bigger brains and

diverse food (wheat,

rice, potato, etc)(Source: www.google.com) 258

Future HUMANS

Four Ways We May or May NOT

1. Human evolution is dead

2. Humans will continue to

evolve

3. Humans to achieve

electronic immortality

4. New era of evolution awaits

on off-world colonies?

(Source: www.google.com) 259