Beneath the Surface of Colours - Martti Huttunen - ebook

Beneath the Surface of Colours ebook

Martti Huttunen

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Take a tour Beneath the Surface of Colours! A New Groundbreaking Colour Theory This easy-to-read and versatile book finally explains colour phenomena validly and comprehensively and helps the reader to understand the world of colours surrounding us. The book is also an excellent colour information manual for demanding readers and experts. It presents a new groundbreaking colour theory that indisputably reveals, how the prevailing colour theories are not true.

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Contents

For the Reader

Why ’Beneath the Surface’

What is Colour?

From Substance to Brain-Centered Approach to Colour

The Weimar Region and a Physicalistic Approach to Colour

Did Ancient Cave Painters Have a Physicalistic Approach to Colours?

Colours Reside Only in the Soul

Words in Front and Behind Colours

How to Name a Colour?

Do Colours Exist Without Words?

Colour Perception

Colours Are Visual Adjectives

Environment as Primary Factor of Colour

Colour Vision Disorders

Levels of Effect and Meaning in Colour From Universal to Particular

Archaic Level 1

Archaic Level 2 (Neuropsychological level)

Culturohistorical Level

Social Level

Cognitive Level

Emotional Level

Colour Research: A Multidisciplinary Science

Colour Theories Through the Ages

Methods Develop and Research Continues

Interpreting Theories and Understanding Colour Phenomena

Colours and Their Mixtures

Additive Primary Colours

Subtractive Primary Colours

Optical Colour Formation

The Pointillist’s Problem: How to Interpret the Theory

Reddish Greens Exist

Additive or Subtractive?

Structural Colours

Metallic Colours

Why is the Sky Blue and What Creates an Afterglow?

Aerial Perspective

Maintaining the Appearance of Colour

The Fastness of Colour

Colour Constancy

Metamerism

Needs May Differ

Fluorescent Substances Increase Brightness

Are Meters Lying?

Blueshift

The Blueshift is an Archaic Automaton

Why Blue Makes Yellow Turn Green?

Why Yellow Becomes Greenish When Darkened?

Yellow Glasses Brighten the World

There is No Colour Illusion

Shadow Phenomenon

The Real Illusion

The Disappearing Colours

Blind Spot is Not Blind

Inverted Colours and Coloured Afterimages

What Causes Coloured Shadows?

Can a Colour Be Registered?

Aesthetics of Showing and Concealing

Valuable Items and Value of Items

Beauty is in Eye of the Beholder

History of Colour Symbols

Colour as Merchandise

The Blue of Babylon

The Colours of Pompeii

Virgin Blue

Poison Green

Purple

Saffron Yellow

The Red Blood of the Blue Bloods

Interior Colours

From Naked Ape to House Human

Lighting and Colouring Interiors Naturally

Light-Coloured Interiors Save Electricity

Function Guides Colour Choices

Ergonomic Aesthetics Economico-Ecologically

Colours in Working Environment

Red Light in Workspace

The Green Oases

Colours and Cultural Landscape

Public Facades

Tar, Lime, and Red Ochre

Yellow Replaces Red

Colours Get Lighter

Colours of Buildings Become Established

New Technology – Familiar Colours

What Tradition Has to Offer

Colours in the Collective Consciousness

Colours in Communication

Colour Charts Deceive

Simultaneous Contrast

Colour Combinations: What Do They Express?

Elements of Colour Contrast

Demanding Display Screens

Heraldic Colour Rules

Road Safety and Colour

Views to Invisible: Infrared Radiation

Dark Surfaces Consume Light

Protective Colours for Autumn Deer Hunting

Colours of Animal Kingdom

How Do Animals See Colours?

Advantages of Colourfulness and Colourlessness

Camouflage Colours

Not Only Colour Communication

The Unknown Ultraviolet

How Would Ultraviolet Look Do a Bird?

Animal and Plant Coexistence

Inverted Colour Theory

Theories to Explain Universal Phenomena in the World

Towards Usable Colour Theory

Complementary Colours Belong to Colour Theory History

Inverted Colour Phenomenon in Visual Image

Principles of Colour Perception

Colour Glossary

Further Reading

Attachments

Appendix 1: The NCS Colour System

Appendix 2: Ecclesiastical or Liturgical colours

For the Reader

We usually take for granted that the world around us is full of colours, but we focus our conscious attention to them only when they appear surprising or unusual. In everyday life, encountering colour phenomena and pondering the essence of colour may have brought to mind, for example, some of the following questions:

What colours really are?

Why the environment seems to alter colours?

Were there colours before there were eyes?

How do animals see colours?

Why colour maps cannot always be trusted?

What kind of colour was Acid green?

Why colours on a computer screen and on print never seem to match?

What is the essential difference between CMYK and RGB colours?

Why does yellow turn greenish when it is darkened?

What do metamerism and colour constancy mean?

Is the blood of the aristocracy (the blue blood) really blue?

Why do Christian bishops wear purple silk shirts?

How do colours affect us, and where do colour symbols derive from?

This book will provide answers to the above and many other exciting questions about colours. At the same time, the reader has an opportunity to see and experience colours and colour phenomena in a new and interesting way beneath the surface.

In this book I will examine the rich world of colours from as many viewpoints as possible. I will also outline some theoretical models that have been developed to understand colour phenomena. A qualified theory can remove the discrepancy between the theoretical and the observable and, thus, explain colour phenomena in an understandable way. This can benefit all colour education when both students and teachers can have a scientifically credible base to build their colour studies on.

For their encouraging support to my theoretical views, I would like to thank Professor Göte Nyman from the University of Helsinki Department of Psychology and art specialist Professor Antti Hassi. I would also like to thank my good friend Professor Paavo Castrén and my long-time associate Doctor Matti Jäntti for the many interesting discussions we have had and for verifying some of the facts in this book. I also thank warmly my close friends Päivikki Kumpulainen, Pertti Nummi and Harri Lahikainen for their assistance, and Jaap Hollenberg for his help in verifying the historical facts of colour use.

My thanks for expert help in aspects related to light and colour measurements go to Leif Riipinen and, for identifying certain rock types, to Geology Professor Martti Lehtinen. I would also like to thank the helpful staff of Suomen Gallup Ltd. for processing some of my research data.

My biggest thanks go to my sons Sampsa and Kaapo, and especially to my wife Marja. This book would not have been written without their criticism and encouraging support.

I dedicate this second edition of my book to my grandchildren Inari, Otto and Leo, and wish them a fruitful and colourful future.

Martti Huttunen

(First Finnish edition: WSOY 2005)

Why ’Beneath the Surface’?

It is easy to hold true something based on concrete evidence and reject beliefs based on unproven claims.

When Interaction in Color, a textbook by painter Josef Albers for teaching colour perception to painters, was published in 1963, it was welcomed enthusiastically by painters and other people interested in colours. Especially, from the point of view of colour education, the book provided a great deal of visually ambitious content. It contained beautiful colour tablets, and different types of exercises helped to illustrate, how the environment changed the appearance of colours. In his book, Albers drew conclusions about the relativity of colour and called the phenomena ’colour illusions’.

This can be seen, for example, in his comments about individual colours: ”Why does colour deceive? Why does colour look different than it actually (physically) is?’”(Albers 1963, page 30). And to theses questions, he offered a multitude of answers. The visual examples in his book helped to bolster the false claim that we somehow see colours incorrectly. This false idea can be found in many books dealing with colours and colour vision – even in sources that should have, by now, excluded the claim as unscientific.

Although modern perceptual psychology has already for a long time held colours only as visual sensations, as interpretations of the human brain, there are still textbooks that use this classic example (see the pictures below.) to prove that we do not see colours accurately. Colour images in Josef Albers’ books have also been used as evidence for the unreliability of human visual perception.

When a pencil is placed on top of the circle, the grey halves of the circle no longer look alike. This example has been used to give us the impression that our visual perception is somehow unreliable.

Nevertheless, when encountering this sort of evidence, the reader should stop and ask further questions: Which grey side of the figure do we see inaccurately? The one with a darker or lighter background? And if the side with a darker background (the one in ‘shade’) appears inaccurate, is it because we have been taught to think that a white background does not affect the appearance of colours at all?

What these kinds of examples have been used to prove as illusory, actually shows, how accurate and advanced the human visual perception is. It also gives us an example of a phenomenon that I call shadow effect, which is one of the fundamental principles of our colour vision. In this book, these examples will be used to explain a variety of colour phenomena.

Harsh living conditions have always eliminated nonviable individuals. Natural selection has also guided the evolution of vision: An individual with a distorted colour vision would hardly have survived and passed on his/her genes to future generations. For this reason, the human visual perception and colour vision can be regarded very advanced and functional.

Throughout the years, various theories and opinions have been used to explain colour phenomena. The best-known and most widely used (apart from Josef Albers’ theories) has been the colour system created by Johannes Itten (Kunst der Farbe, 1961; The Elements of Color, 1970). Many people have felt that Itten’s views about colours are clear, simple, easy to understand and, at a first reading, even logical. With a closer look, however, one can see that the so-called theoretical laws about colour phenomena and ‘colour harmony’ presented in the book are not based on any scientific framework. There is simply no empirical evidence to support them.

A modern, educated reader, who observes the world around her with a critical eye, is no longer happy with explanations, such as “[t]he rule of complementaries is the basis of harmonious design because its observance establishes a precise equilibrium in the eye.” (p. 49) or “[t]he eye demands the complement to a given hue.” (p. 62). What does the rule of complementaries dictate? What is the precise equilibrium in the eye? What does it mean that the eye demands complement hues? Surely, there must be more plausible explanations to colour phenomena.

Working as a lecturer of colour theory for more than 20 years after my revered teacher, painter Onni Oja, at the University of Industrial Arts Helsinki gave me an opportunity to familiarise myself with the prevailing views about colours and the content and methods used to teach them. My growing curiosity over the mechanisms of colour phenomena very soon made me realise that much of our so-called knowledge about colours seemed to be based on mere beliefs and contained visible discrepancy between the theory and the observable reality. For this reason, I saw it appropriate to examine one of the problem areas in more detail, and decided to conduct a study on people’s assumptions about colour harmony (”Testing Johannes Itten’s hypothesis of a colour contrast theory in a spontaneous choice situation” / ”Johannes Ittenin väriharmoniaopin hypoteesin testaus spontaanissa valintatilanteessa”, author’s unpublished research material). The results proved to be interesting. According to Itten’s theory, the 397 subjects involved in my study should have experienced certain colour combinations as harmonic and rated them positively (+). Nevertheless, the vast majority of subjects gave these combinations negative ratings (-) and, moreover, the subjects’ answers did not provide any support to Itten’s theoretical arguments about colour harmony.

Most of the people who participated in my study were art students oriented towards visual arts, and almost all of them had been introduced to colour theories already in elementary or high school.

So, based on my research, Itten’s colour harmony model seemed completely inaccurate – at least in a situation of spontaneous selection. I also quite soon began to suspect that other colour theories based on a ’physicalist’ idea of colour were standing on a fairly shaky ground too.

Getting to know Edwin Land’s Retinex Theory, also supported my own critical standpoint towards the various ’theories’ applied in colour education at that time: Those theories were not to be taken seriously and, to my mind, they were merely pseudo-scientific nonsense. The final thing that convinced me of the legitimacy of my suspicions was an article written by Professor Veijo Virsu in the University of Helsinki’s journal ’Yliopisto’ (13/92). Virsu’s article was titled

”Goethe’s colour theory is unscientific nonsense” and in it the author stated for example that ”in the history of science, Goethe’s approach is a cautionary example.” And that “as science, [Goethe’s] research is like a counterfeit coin among genuine ones.”

After all this, I find it necessary to ask the following question: How many of us would really like to practice self-deception or, as a teacher or lecturer, deliberately deceive others by turning a blind eye to clearly observable facts?

In this book I handle colour pigments and their evolution very little, apart from some examples in chapters dealing with colour symbolism. Although the subject is very interesting, there is already a lot of information available about them. Neither does the book contain a psychological colour key, a verbal definition of different colours and their meaning, which probably is familiar to most readers from other colour literature. This is because I am certain that a verbal definition of a colour tone without a colour sample and an example of its use (i.e. its context) is bound to produce only vague mental images in the reader’s mind and, therefore, lead to misinterpretations.

A hue, which in such a list is called, for example, sky blue, rose red, brick red or olive green, is, regardless of its very accurate-sounding verbal definition, still completely undefined visually. No two people will get the same mental representation of a hue based on just its name. Verbally defined colour is always dependent on individual experiences and interpretations.

Surely, colours can be said to have many expressive features and functions. Nevertheless, it is totally impossible to say, for example, that a certain purple colour sample represents great ’honesty’, ’distance’ or ’reliability’, unless, at the same time, the colour is presented in such a social, historical and cultural context, where the claim can be evaluated.

It’s not a visual illusion that, in this image, we see the grey circles as truly different colours, although, from a physicalistic viewpoint, the circles have been printed similar and their CMYK values are exactly the same.

What is Colour?

From Substance to Brain-Centered Approach to Colour

Colours are such an obvious and mundane part of our environment that we don’t begin to think about their essence before somebody asks us what they actually are. The most common answers define colour as light, a reflection of light or a wavelength. Sometimes, colour may be defined as a feature of light. These responses show that the person has faced the question before or that the answers have been adopted during some degree of colour education. The answers of people with experience in painting or dyeing almost without exception reflect a view that colour is something material. This material nature of colour in our language can be seen in how we usually mean the same thing with words colour and paint. These words are very often used interchangeably. When we look at the history of colour theories, we can see that the approach to the essence of colour has mainly been guided by a substance-centred (materialistic, physicalistic) approach. Even though, over time, ever more systematic and accurate definitions and classifications of colours, and various colour systems, have been devised. (See Colour Research: A Multidisciplinary Science, p. →, as well as Colour Glossary: Colour systems.) In the smost advanced systems, the colours are placed in the system’s internal colour space, the so-called colour atlas, based on the traditional colour characteristics, such as, hue, darkness (or lightness) and saturation.

Contemporary notions about colour indicate that a physicalistic approach, that sees colours as something material, still prevails (see Colour Glossary: Paradigm). This notion can be seen underlying many colour systems and theories based on them. Now that colour research has progressed from studying substances and wavelengths to the study of human visual system, the notions about colour can be divided into two main groups:

Physicalistic

, materialistic or substance-centred approach, a paradigm in which the different manifestations of colour are objects belonging to the physical world and residing outside the perceiver. As ’objective facts’, they can be measured using various measuring devices.

Humanistic

, perception or brain-centred approach, a paradigm in which colours are not objects outside the perceiver, but signals produced by the human visual system and interpreted by the brain. This is how, for example, the Greek philosopher Democritus saw the essence of colours.

The Weimar Region and a Physicalistic Approach to Colour

Germany, and in particular its Weimar region, has been in an interesting and important role in the development of Western colour systems and classifications. Probably the most important founding father of the physicalistic school of thought was Johann Wolfgang von Goethe (1749–1832) with his colour ‘theories’ (Die Farbenlehre, 1810, and Geschichte der Farbenlehre, 1812). The Weimar tradition can clearly be found on the background of the Western colour education.

One of the art schools operating in Weimar during the 1920s was Bauhaus, where the approach to colour resonated Goethe’s views. The Goethean tradition within the Bauhaus school was further developed by painters and teachers Johannes Itten and Josef Albers, and, in his own and peculiar way, the Russian-born painter Wassily Kandinsky.

Also Rudolf Steiner (1861–1925), a mystic inspired by Goethe’s views and Eastern religions, developed his own Anthroposophical colour theory. According to Steiner, colours, just like celestial bodies, had supernatural and even cosmic powers.

Goethe´s views appear to have influenced also some serious German colour research. One of the most influential German scientists studying human vision was physiologist Herman Helmholtz (1821–1894), who continued and completed the theory of human colour vision by Thomas Young (1773–1829), known today as the Young–Helmholtz theory. Also the German psychologist and physiologist Ewald Hering (1834–1918) has influenced the development of so-called Opponent-Process theories, as well as, Johannes Itten’s materialistic and substance-centred approach and its theoretical justification.

Joseph Albers, an artist who fled to United States from Nazi Germany in 1933, also based his views on Goethe’s physicalistic approach, when he taught colour interaction phenomena to painters. Although Albers emphasises in Interaction of Color, his excellent book for painters, that colour is not so much a physical, but rather a psychological phenomenon, his physicalistic approach is revealed in the way he presents and analyses colour phenomena as colour illusions. According to him, the human vision deceives and only produces illusions of reality, and there is a big difference between physical facts and psychological perceptions. This means that Albers, too, saw colours as physical objects whose appearance is always distorted by the presence of surrounding colours.

When we look at colours in our environment, they very easily seem to belong to the physical world and its objects. For this reason, it is tempting to think that also colours are material and, therefore, somehow physically objective. This is the view of many physicists, for example.

For a painter, paint is a concrete substance, which, when transferred from a palette to a canvas, begins to interact with other colour surfaces in the painting and, at the same time, its appearance can change significantly. The change in appearance, however, is not an optical illusion, although some people tend to think that way. One of the aims of this book is to explain these colour interaction phenomena as clearly as possible

One interesting set of beliefs are the stone and colour therapies based on oriental understanding of colour. These beliefs hold that certain coloured substances emit ’colour radiation’ with magical forces. Gullible people can, for example, buy coloured ‘therapy stones’ to be place under the pillow to emit healing powers – or, at least, peace and relaxation – during the night. Without any light in complete darkness, that is.

Naturally in this case, autosuggestion is the only power that can help the superstitious, not some colour radiation. People believing in the spiritual and therapeutic magic powers of stones and dyes could as easily believe that they caused cancer – just like holding a piece of uranium under their pillow.

Did Ancient Cave Painters Have a Physicalistic Approach to Colours?

Probably already in the Stone Age, some 35 000–10 000 years ago in places like Altamira, Lascaux, Chauvet, and Cosquer, early cave painters pondered the material nature of colours, as they looked for suitable materials for painting. The material properties of pigments, such as hue and durability, must have become familiar to these people in practice. Some pigments did not keep their colour, while others lasted from generation to generation.

The Astuvansalmi rock paintings in Ristiina, Finland date back 5000–6000 years.

The Altamira cave paintings in Spain are 14 000– 9500 years old.

The paints used during the prehistoric period, the so-called earth pigments, were made from minerals that were easy to find from the ground. Of these, the most common were yellow and red ochre, dark brown manganese oxide, carbon black, and white powdered bone. It took thousands of years before the painters gained access to other durable pigments, such as, blue lapis lazuli and azurite and green malachite minerals.

From the perspective of ancient painters, a physicalistic approach to colours seems very natural, even human (see Colour Glossary: Earth pigments). Now afterwards we can play with the idea that, if the ancient cave painters had had durable bright red, blue and yellow pigments, the images in their limestone cave galleries would look completely different. Through those images, we could even have a better understanding of our ancestors’ thoughts, beliefs and view of the world.

Colours Reside Only in the Soul

Even the early philosophers have been known to contemplate the essence of colours. More than 2400 years ago, the Greek philosopher Democritus, who argued that the world consists of undividable atoms, contemplated colours and painting. In his philosophical reflections, he came to a conclusion that colours reside only in the human soul. Regardless of his materialistic worldview, Democritus’ non-materialistic and mind-centred assessment was vastly ahead of its time. Many people are still to understand this very early but fundamental notion: colours are visual sensations and, therefore, only belong to our brain.

In this book, the theoretical explanation models of colour phenomena are in principle based on the aforementioned basic idea. A summary of the theory is presented at the end of the book in the chapter Inverted Colour Theory.

To recap:

Which colour pigments did Stone Age cave painters mainly use?

How do people, who believe in stone and colour therapy, understand colours?

What are the two main categories contemporary approaches to colour can be divided into?

What is a paradigm?

Words in Front and Behind Colours

In its own way, our understanding of colour and, particularly, the significance of colours to humans, can be seen in the way we have named them. A dear child, such as colour, has many names. The way colour names have evolved reflects how languages have evolved. At first, languages had very few names for colours, if any. Probably first evolved just words signifying dark and light.

Colour names are often loan words from other languages. For example, the word ’orange’ arrived into the English language as late as in the 18th century with the arrival of exotic fruits from British colonies. When an ancient Finn used the word ‘fire-haired’, he meant that the object was red. The Finnish word for alder (leppä) has meant ‘red’ or ‘blood’. This is because when alder bark is peeled off during springtime, the layer underneath turns blood red due to oxidation (cf. Finnish väri and Swedish färg [colour] and Finnish veri [blood]).

Today the English language has just 12 non-compound words that are used to name only colours. These are black, white, grey, red, green, blue, yellow, brown, purple, pink, magenta, and cyan. These are also the ones that we can easily group as separate hues. These hues can also be called memory colours, because we can easily divide the perceived colours into these categories.

The most significant colour humans can perceive is red. This can be inferred from the mere fact that 2/3 of the rod cells on our retina are sensitive to red light. Red has also played an important role in the world of the early humans. Tombs with human corpses with red mulch scattered on them or even corpses painted with red paint have been found in archaeological excavations. This kind of colouring of dead bodies was performed by the early Neanderthals (Homo Neanderthalensis) in Europe before the modern man (Homo Sapiens) arrived from Africa. Neanderthals seem to have though that the red colour had a supernatural, magical and revitalizing effect. Some archaeological excavations have found traces of even earlier uses of red dye.

The Finnish-born artist Haddon Sundblom drew a red Santa Claus to the promotional images of a well-known beverage company in 1931. After that Santa has been red all around the world in cultures where Christmas is celebrated.

Red is a colour to which even a small baby reacts to. In many languages, the word for red has appeared immediately after the words for dark and light. In the early use of the words for red, they signified mainly orange, red and purple hues. In some languages the significance of red colour can be seen in the fact that the root in the words for red and beautiful is the same, in the Russian words beautiful (krasivyi) and red (krasnyi), for example. In some Finno-Ugric languages the word for beautiful also means red. The Finnish word for brown (ruskea) has originally meant red. When the Finns said iltarusko (a word for sunset afterglow), they expressed that the sunset was both red and beautiful. The Finnish phrase verenruskea (blood brown) has meant that blood is red.

How To Name a Colour?

Many familiar colour characteristics, such as tone, density, and purity, can help name and verbally define colours. Colours also have visual qualities that seem (and feel) warm or cold to us.

Orange and cyan are each other’s opposites on the cold–warmaxis. In reality, the correlation between the name and the actual visual qualities of a colour are quite arbitrary. One way to verbally understand and express the features of a particular colour is to define it in relation to its neighbouring colours on a colour wheel, such as the NCS colour wheel on page →. The assessed colour always belongs to one of the four main colour areas. After the main area has been defined, we can begin to compare the colour to the neighbouring colour areas. We can say, for example, that the colour in question is bluish-green or greenish-blue, depending on which of the two main areas the colour seems to belong. The verbal definition of a colour’s saturation and darkness is a much harder task. One visual solution to this problem is the so-called Colour Triangle (see for example NCS system on page →).

Do Colours Exist Without Words?

One of the main arguments of this book is that there are no colours without eyesight. However, sometimes it has been thought (and citing a number of ‘studies’ even claimed) that we would be unable to see colours without the existence of words to describe them. Monkeys, unable to speak, must then be colour blind. (Though, they aren’t.) If a language doesn’t have a name for a particular colour, it in no way proves that the speakers of that language cannot see that colour. Such colours just haven’t been so significant in the everyday life of that culture that they would have been named.

It has sometimes been proposed that the ancient Greeks would have been colour blind to blue, because their language didn’t have a word for it. Nevertheless, colour blindness can be ruled out as an explanation. The Greeks were, of course, able to describe blue by using familiar parallels, such as ‘the colour of the sea’ or ‘the colour of the sky’. This is what we do anyway when we speak about colours anyway. If we want to specify a colour hue, we begin to search for familiar references from our common surroundings: grass green, blood red, mouse grey, jet-black, etc.

To recap:

Which colour does a small baby first reacts to?

Which English non-compound words are used to name only colours?

What does the argument ’There are no colours without eyes’ means?

What was the original meaning of

blood brown

in the Finnish language?

Colour Perception

Colours are Visual Adjectives

Colour vision is a complex series of neuropsychological events in the human brain that creates colour sensations from a variety of external and internal stimuli. Although colours seem to be a part of the outside world and its objects, it is important to understand that the colours we see in our environment are only products of our brain interpreting the world around us; things that only our brain can possess

In a visual event, the brain does not assume the colour of an object to change, not even under varying lighting conditions with various lights and shadows. Nor do we think that objects change their shape, when our viewing angle changes. Colours are attributes of objects’ quality, and we can, therefore, call them visual adjectives. Throughout the times colours have, in a few hundredths of a second, expressed to us the quality and usability of objects in our environment.

Antelope and Homo erectus, the upright man.