Anatomy & Physiology

The Muscular System

Read My Lips!

1. (Name) Can you name the muscle indicated by this

line in the diagram? Orbicularis oris.

2. (Classify) Under which system of naming muscles is

Orbicularis oris named? It is named according to

what it looks like and where it is.

3. (Describe) How would you describe the unusual

appearance of the lips? They are pink and they

protrude from the face, etc.

4. (Compare) How does the appearance of the lips

compare to the appearance of the other muscles of

the face surrounding them? They are redder.

5. (Infer) What would you infer about the relationships

between the structure of the lips and the function of

the lips? That structure defines function, that is,

they are designed to suit their job description.

6. (List) Can you list the functions of the lips? They

sense temperature and texture of foods in order to

protect our inside living tissues, so we don’t eat

something that is too hot or sharp or hard, or has

a lot of moving legs like a centipede. They help us

articulate sounds during speech. They help us

acquire food through the use of suction as nursing

infants, and…Oh yeah, lips are for kissing.

7. (Classify) What kind of kisses are there? Some

kisses demonstrate nurturing and some kisses are

more sexual.

8. (Speculate) How did kissing, which is such a

widespread human behavior throughout the world

today and throughout history, get started among

humans? What is the anthropological origin of the

kiss as a human behavior? Most students will

hypothesize that kissing is more about nurturing,

while others will hypothesize kissing is more about

sex and reproduction.

9. (Indentify) Can you identify the type of kissing

behavior in the video clip (Nova Video: Mystery of

the Senses – Touch), and identify the tribal African

and tribal Asian persons doing the kissing?

Nurturing kissing. Two mothers, one sister.

10. (Analyze) Can you analyze the kissing behavior

demonstrated by the mothers and sister in the video?

The mothers and sister are using kissing (kiss-

feeding) to feed infants and young children.

11. (Classify) How would you classify that kissing

behavior? Nurturing.

12. (Formulate) Based on your analysis of the data

from the video clip, can you formulate a theory

that answers the question: What is the

anthropological origin of the human kiss? It is a

nurturing behavior designed to feed pre-

masticated food to infants and small children

with baby teeth and weak jaw muscles. The

behavior is an adaptation for survival of the

human species.

13. (Apply) How can you apply your theory about the

anthropological origins of the kiss to explain the

difference in people’s lips? If kiss-feeding is an

adaptation for species survival, and structure

defines function, then the members of the human

communities whose lips function in kiss-feeding,

should have lips structurally adapted to the task.

14. (Recognize) Who in natural human communities is

most likely to be involved in the nurturing behavior

of kiss-feeding? We saw examples of mothers and

a sister in the video, but in other offspring-

nurturing behaviors the individual with the body

parts (uterus, breasts) to do the nurturing of the

offspring does the nurturing. In seahorses, the

male broods the offspring because he’s got the

pouch for it.

15. (Infer) What would you infer to be true about the

lips of those adapted for kiss-feeding? Lips that

are proportionally fuller, more supple, and

thinner-skinned in order to be more sensitive to

the touch should be better for kiss-feeding. Being

thinner-skinned should also make them appear

redder, like women’s lips seem to be.

16. (Support) What further evidence is there that

supports the conclusion that having fuller, more

thin-skinned, and therefore redder and more

sensuous lips (which are better adapted for the kiss-

feeding of children) is a feminine characteristic?

Both women and men demonstrate behaviors

that accentuate their masculine or feminine

characteristics, especially to attract attention

from members of the opposite sex. Women wear

lipstick to make their lips look fuller and redder,

and to draw attention to them. Women will even

sometimes endure plastic surgery if they feel

their lips aren’t full enough, etc.