Don’t snicker, it’s true! Lashes are the boob job of the new millennium. Everyone wants bigger, darker, longer, thicker, and sexier lashes. That come-hither look that’s sported by starlets like Hayden Panettiere and Liv Tyler doesn’t come without a little assistance. So how do you get the eye lashes that your best friends will envy? Well that’s the easy part.

Longer, Thicker, Fuller Lashes

Stars like Hayden Panettiere owe their lashes to lash growing solutions like Revitalash that grow your own lashes thicker, longer, and add natural curl. With just a swipe a night anyone can have the lashes they dream of. And at only $150 a tube it’s far more cost effective than spending $200-$500 for lash extensions every month that need special care!

How They Work

Products like Revitalash use glaucoma medication as a means to stimulate growth. The medication has been approved and tested by the FDA to help glaucoma sufferers. One of the benefits discovered from people using the medication was eyelash stimulation! Companies like Revitalash use the active ingredient from the glaucoma medications and mix it with conditioning solutions to help not only stimulate growth, but improve the lashes. No matter how brittle, fine, or short your existing lashes are, conditioning and stimulation will help them look better in a month.

Safety First

Not all eyelash growing solutions are created equal. I trust Revitalash since it was created by an eye doctor for his wife who lost her lashes to cancer, but if you are looking at another brand you need to do your own research. What I do know, is that most solutions are safe, and that the active ingredient has been approved by the FDA for use in the eye.

What You Need To Know

Lash growing solutions take about 30 days to see results, but many people tell me they see a difference after 2 weeks. A single tube of Revitalash will give the average person about 3 months of use. Many people get their lashes to the thickness and length they want then back down to using the solution only 3-4x a week to maintain the lashes.

If you stop using Revitalash your lashes will not fall out! They will probably go back to the way they were before you started using the solution, but you won’t be bald. Also, people should realize that when you are stimulating faster hair growth, you are speeding up the hair cycle. This means when you first start using Revitalash you will probably notice more eyelashes falling out. This is because you are “shedding” your old lashes faster to make room for the new ones.

Darker and Fuller

A darker eyelash not only creates the illusion of a fuller lash, but also gives the lashes definition. You can use mascara to paint the lashes. If you chose this method I highly recommend “tubing” them instead with Blinc. Blinc creates a tube around the lash that gives the wearer the same benefits as water proof mascara, but without the damaging results. It also “plumps” the lashes, doesn’t smear, smudge, and actually helps condition the lashes…which we all know is vital to lash health!

You can also dye the lashes with a safe eyelash tint. There are many on the market, but only a few have been proven safe for they eye area. I personally use a vegetable based dye in either black or dark brown that is safe for they eye area and won’t blind anyone if it gets into the eye. Lash tinting runs about $25 and needs to be done once a month just like hair coloring. Most people want their lashes black, but trust your technician. I like dark brown on people who need to warm up their skin tone. Black is very cold, but dark brown which is almost black, will warm a blonde or redhead right up, making their eyes brighter and skin color richer.

Eye Brows

Interestingly enough…all the above statements can be used on the eyebrows as well, so if you are looking to get a thicker, fuller brow, speed up growth after over plucking, or want to tint your brow hair, you are seeking the same products and services!

So the number one eyebrow question I’ve been getting is on training your eyebrows. In an article I wrote Eyebrows Only, I touched on this, but let’s get down to the nitty gritty of what needs to happen.

Training your brows is easy, but it takes time and dedication. If you’ve ever had to train your hair to sit in a different part or hair style then you already know this. What many people don’t realize is that eyebrows are hair, and therefore can be trained like any other hair on the body.

The tools you need to train your brows depend on what problems you are working with. Gel is the most common tool used. Fancy eyebrow gels are on the market and many of them are great. My favorite is Brow Fix from Jane Iredale, but there is nothing wrong with using your regular hair gel for your brows. The only difference between the two is usually packaging, and eyebrow gels are proven safe for skin and eyes so you won’t get any breakouts or red eyes. If your eyebrow hair is really curly, course, or sticks straight out then you are going to need something more powerful to start with and eyebrow gel isn’t going to cut it. Get a firm hold gel, or a hairspray to hold the hair in place. You can also use a heated lash curler as a flat iron. Since the curler is designed for the lashes it won’t burn the skin, but it can help arrange and flatten wild brows.

An Eyebrow Brush is essential for everyone. I personally like the Spoolie versions which are like the brush in your mascara wand, but you can use one like in the picture at the top of this article. This tool is used to brush the brows and place them.

Growth solution like Revitalash, LiLash, or one of the many other lash growth solutions on the market. These will help grow brows faster, thicker, and help fill in holes. If the hair follicle is dead this type of product won’t help, but for many it’s just what they need to get those brows a growing!

Your finger is the final tool. You will need it to stroke, lay, and press your hairs into place.

Problems and Tools

Hair sticking up, curling, or not laying in place
Tools: Gel, Lash Curler, Brush, Finger
What to do: Using the brush decide how you want your hair to lay. Use a lash curler to heat them into place. Once that looks good, place gel or hairspray on your finger and apply it lightly to the brow hair. Use just enough to get the hair to stay in place. You can use the brush again to help lay them down once you’ve applied the gel or spray with your finger. Also, when you don’t have the gel on, you can use your finger to just gently smooth the hair into place. This will help it too.

Hair Not Growing
Tools: Growth solution, Finger
What to do: Use the growth solution on the area that needs help. REMEMBER that if you apply this solution it will grow in more hair and faster. That means if you took out all your brows and now are applying it to the entire brow area…well be sure you want hair in all the areas you are applying it! You also need to take your finger and rub over the area you want hair. Rubbing stimulates hair growth!

That’s it. Simple. Just remember, patience, diligence, and time.

To best understand what makes a product effective you need to be able to read a label. Anyone watching what they eat will tell you reading the labels allows them to know exactly what they are getting and make educated choices on what they put into their bodies. The main problem with reading skin care labels is that most of us know what partially hydrogenated soybean oil is, but we don’t know what Dimethicone 350 is and what it does. This makes reading skin care labels very difficult, but there are a few questions you should keep in mind:

• What are the Active Ingredients?
• What does this Active Ingredient do?
• Is there enough of the Active Ingredient in the product for it to work?
• Does the product’s formulation allow Active Ingredients to penetrate the skin?
• Do any of the inactive ingredients (the other stuff) interfere with the effect of the active ones? Do they have the potential to harm the skin, e. g. by causing allergic reactions, irritating or dehydrating the skin, clogging pores, etc.

Some of the above questions I will address in another part of this series, but much of the above info can be found in a product label if you know how to decipher it. I am not going to delve deeply into the FDA laws on labeling since they are complicated, and most cosmetic companies ignore them anyway, but I am going to give you a basic run down of how to read a label.

Breaking Down A Label

So lets start at the top. Active Ingredients. An Active ingredient is the substance that is pharmaceutically active. In other words, what makes the product work. We all want to effect changes in our skin and the only way to do that is to use products that have ingredients designed to target specific problems.

In this label the Active Ingredient is Salicylic Acid 0.5%.

The next part of the label is a laundry list of what makes up the product, including the Active Ingredient.

You might notice that Salicylic Acid is almost at the bottom of the ingredient list. This is completely normal. Most products are made up of water and other ingredients that create feel, smell, slip, color, and preservation. A good manufacturer will carefully chose these other ingredients to enhance the Active Ingredient and help get you the end result you seek, but many manufacturers use cheap filler substances to sell to your senses, or just plain trick you. My favorite example of this is menthol. A client will come in and tell me that they “feel” a product working. When I look at the label I discover that what they are feeling is menthol – a key ingredient of Vapor Rub – tingly on the skin. Trust me, it isn’t doing anything but making you “feel” like the product is working.

Although the US federal regulations require ingredients to be listed in descending order from most to least, the FDA doesn’t require that a distinction be made between active or inactive ingredients. Also, any ingredients with concentrations below 1% may be listed in any order the manufacturer sees fit. This means that the top third of the ingredients listed generally consist of around 80-90% of the entire product, the middle third represents around 5-8% of the product, and the bottom third represents 1-3% of the total product. Doing this math is easier than you think. Let’s work with the 22 ingredients in our sample product label. We take our 22 ingredients, divide them by 3, and get 7 1/3. So we can estimate that the first 7 ingredients make up 80-90% of the total volume of the product.

An easy trick for comparing products is to compare labels. Start by counting how many total ingredients are listed on each product. Try to chose products that have close to the same total number of ingredients. Then count down from the first ingredient until you reach your Active Ingredient. If you find your Active Ingredient listed as #8 on one product and #10 on the other product, then the #8 listing is the product that contains more of the Active Ingredient because it is closer to the top of the label. But remember that this trick is useless if the ingredient you seek falls into the bottom third or 1% of the label because these ingredients can be listed in any order.

Now that you have the basics of reading a label let’s learn to chose the correct ingredient with the correct amount of oomph!

The hardest thing I face in skin care is really the same thing everyone else does – the sea of products, product claims, and pricing. Luckily as an “expert” it’s my job to immerse myself in product knowledge. This means that in a normal month I spend about 12 hours researching new products, learning about cosmetic chemistry, dissecting new ingredients, and testing new product lines. To some this may sound very exciting. All those creams, lotions, and potions. But anyone who has seen my skin after a bad “testing” can understand why I as a professional frown upon anyone testing a new product on themselves without my go ahead. It isn’t that I’m a control freak…well maybe a little…but mostly it’s due to the fact that unless you understand product ingredients, cosmetic chemistry, and labeling, then you are playing Russian roulette with your skin and wallet!

So let’s get down to it. What the heck makes the $10 cream found your local drugstore different from the $50 cream found at a department store, different from the $50 cream found at a dermatologist or esthetic office? Heck what makes the $50 cream I sell different than the $200 cream another person sells? Well a lot. An awful lot. And an awful lot that is hard to describe, but I’m going to try anyway. By the end of this series of articles we will have covered all the pieces that makes product quality different/better/worse:

• Type of Ingredients
• Active Ingredients/Amount of Active Ingredients
• Ingredient Processing
• Delivery Systems
• Studies/Research
• Packaging/Advertising

But before we get to all that we need to understand the anatomy of a product. To understand the quality of a product you must be able to read a label, and to do that you need to understand the major categories of what makes up a product. This list is compiled thanks to www.smartskin.com.

Antioxidants: Antioxidants are substances that neutralize free radicals. Damage by free radicals is one of the key mechanisms of the aging process. Also, free radicals mediate many forms of inflammation. Antioxidants reduce the skin’s exposure to free radicals. Not all antioxidants are created equal, they vary by the range of activity, solubility in oil and water, and other properties.

Active Ingredients: An optimal skin care product should contain one or more active ingredients in an effective concentration. These are the ingredients that actually do something to the skin. For example Retinal or Vitamin C would be an active ingredient.

Binding Agents: Substances that hold products together and prevents separation of the water and lipid components. The most important binding agents in skin care are emulsifiers.

Emulsifiers: Emulsion is a smooth blend of oil and water. Since most skin care product formulas include both water and oil soluble ingredients, emulsions are very popular in skin care. Most creams and lotions are emulsions. However, emulsions are unstable and quickly separate. Emulsifiers are substances that stabilize emulsions and prevent products from separating.

Delivery Enhancers/Systems: Ingredients that enhance delivery of other ingredients into the skin and/or insider skin cells. This is easily the most important category when it comes to separating the good and the bad products since the delivery system dictates how much product is actually used by the skin.

Emollients: Substances that smooth and soften the skin. There exist a wide variety of emollients, each providing its own individual texture to the skin. This is usually the ingredient that creates “slip” or “feel” which in product lingo mean how the product feels to the user. Often companies spend more money on making a product feel good than making it work since feel sells to the ignorant.

Humectants: Substances that can attract water, usually out of the air. By definition, all are also moisturizers. In fact, any good moisturizer has to contain potent humectants. Serums are comprised of humectants.

Lubricants: Substances that make skin feel smoother to the touch and reduce friction; more common in hand creams. Once again we have slip and feel.

Preservatives: Substances that kill detrimental bacteria, yeast and/or molds, thus prevent spoilage. While some preservatives may occasionally be irritating to the skin, the use of products spoiled by microorganisms may be equally or more damaging. Sometimes antioxidants and stabilizers are also referred to as preservatives because they inhibit chemical degradation of products.

Solvents: Substances, such as alcohol or water, which dissolve other ingredients.

Surfactants: wetting agents, substances capable of reducing the surface tension of a liquid in which it is dissolved. In skin care, surfactants enable a topical product to easily spread and glide across the skin.

Vehicle: The base that carries the active ingredients.

Fragrance/Color: the other stuff that goes into a product to make it more appealing for sale.

Next we will use this knowledge to learn how to read a label.

…will still age you, increase your risk of cancer, and break down your immune system.

A tan is a tan is a tan. Unless it comes out of a bottle it isn’t safe. No if, and’s, or but’s about it. So knowing this. Knowing that all the research in the world has linked sun damage (aka tanning) to the rise of many illnesses and disease, I have to ask myself why my clients are still doing it. The only answer I can come up with is I haven’t educated them enough. So here we go. Please pay attention!

So lets talk tanning. I know summer is here and everyone wants to look good with a “healthy” tan. But trust me, there’s nothing healthy about a suntan. The only safe tan is a fake tan. So let’s start from the top.

UVR or Ultraviolet Radiation

UVR comes in a few different forms, but when talking about tanning we are discussing UVA & UVB which are the rays in sunlight. UVA rays are known as the “aging” rays and consist of longer wavelengths that penetrate deep into the dermis – our “true” skin. UVB rays are knows as “burning” rays. They are shorter than UVA, affecting the top layers of skin – the epidermis.

Suntan (via the Mayo Clinic)

A suntan is the result of injury to the top layer of your skin. A tan develops when UV light accelerates the production of melanin – the pigment in your skin that makes up your color. The extra melanin produced to protect the deeper layers of skin oxidizes and darkens your pigment giving you a tan color. In essence, a suntan is your bodies defense mechanism against UVR rays. While you are tanning, your body is fighting to prevent further injury to the skin, but the protection only goes so far.

Sunburn (via the Mayo Clinic)

Eventually, ultraviolet light causes the skin to burn, bringing pain, redness and swelling. Depending on the severity of the burn, the dead, damaged skin may peel away to make room for new skin cells. Though the symptoms of sunburn may fade after several days, the damage to your skin remains. Sun exposure that is intense enough to cause a burn can also damage the DNA of skin cells. This damage sometimes leads to skin cancer.

People with darker skin pigment are less likely to burn because of the protective action of the melanocytes, which produce melanin. However, even those with darker skin types can burn with repeated exposures to UV light. This intense exposure can produce negative effects in the skin, including dry, rough patches, wrinkling and other skin disorders. So even though people with darker skin can tan and tolerate longer periods of sun exposure without “burning,” the sun can still cause skin damage.

Tanning Beds

Researchers estimate that a twenty-minute visit to the tanning booth is equivalent to spending a day at the beach. And contrary to most claims, there is no truth in getting a “base tan” in protecting against future sunburns. Tanning beds and sun lamps emit 93% to 99% UVA. This increases the speed of a tan allowing for a fast and even tan, but it’s also 3x the normal UVA the sun puts off. This means you are getting 3x the amount of UVA radiation without the usual burn this type of exposure would give you. Let me repeat that because it’s important. 3x the usual amount of UVA radiation, but no UVB to burn you. What does this mean to a tanning bed user? Well it’s the reasoning behind all the tanning bed propaganda like:

“Safer than the sun.”
“Good for your health.”
“Excellent source of vital Vitamin D.”
“Protect against bone loss.”
“Giving you a safe base coat to protect you from sun damage.”

You see, UVB creates immediate damage to the top layers of skin and is therefore considered the “dangerous” part of tanning. At least that’s what these companies want you to believe. Yet, ask experts about even limited exposure to UVA and they will give you hard, scientific data that UVA exposure leads to long-term skin damage such as cancer, DNA destruction, dysfunctional immune system, sun and eye burns, cataracts, and photosensitivity. So tanning bed companies claiming that their beds are “safer than the sun”, “good for your health”, or safe at all is like big tobacco claiming that smoking is safe and good for you. In fact, I often tell my clients that tanning is like smoking. It’s something you chose to do even though you know all the data points to it killing you.

Tanning Beds – The New Cigarette (via Elizabeth Carruth)

Studies have concluded that indoor tanning is directly linked to skin cancer, specifically malignant melanoma, and other numerous health problems. Although tanning industries claim that UVA radiation is safe, medical research disproves this theory. Researchers say that because UVA rays penetrate deep into the skin, they destroy skin fibers and damage elasticity. Long-term effects of UVA rays include premature aging and wrinkles. They are also linked to malignant melanoma, damage to the immune system, weakening of the skin’s inner tissue, and other types of skin cancers… From his research, Dr. David Sidransky concluded that UVA radiation causes the same damage as UVB radiation to skin cells which leads to cancer. In cases where exposure to light was increased, it was more likely that the damage would exceed the constructive, cellular-repair mechanisms, and a tumor would be more likely to develop.

A study conducted in Sweden helps to prove that tanning beds are a major factor in the development of malignant melanoma. Different people, all under the age of 30, were included in the study. The data concluded that the people who used tanning beds more than 10 times a year were seven times more likely to develop malignant melanoma than those who did not use tanning beds as often. The study also concluded that melanoma risks are increased by 300% for those using tanning beds occasionally, and that the risks increase by 800% for those who use tanning beds more than 10 times a year.

A number of various authorities warn the public of the dangers of tanning devices, but if that isn’t enough for you here are some hard facts. A Dermatology Department in the United Kingdom conducted a study examining DNA damage in human fibroblasts cells after they were exposed to artificial tanning lamps. The study showed that it is highly likely that the lamps cause DNA damage that is directly related to the development of skin cancers, cutaneous effects, and damage to the immune system. They believed that the public should be warned about the dangers of using tanning beds. (Woollons, Clingen, Price, Arlett, & Green, 1997) This was in 1997. New studies have conclusively proven these same findings.

A study published by the Journal of the National Cancer Institute in February 2002, found that people who used tanning devices were 1.5 to 2.5 times more likely to develop common kinds of skin cancer than people who did not use the devices. Dr. Madeleine Duvic, professor and chairman ad interim of the Department of Dermatology at M. D. Anderson, said,

“Basically, the ultraviolet radiation given off tanning beds aren’t good for your skin. The longer ray UV-A radiation goes deeper into the skin than UV-B and does not protect you from a sunburn at the beach. Both UV-A and UV-B cause aging and skin cancer just like the sun. Use of phototherapy is immunosuppressive so when it is used to treat diseases, there is increased risk of getting a skin cancer. It’s like a safer cigarette. There is no such thing. There are no safe tans – they are a sign of DNA and skin damage.”

Dermatologists believe that tanning beds are a leading factor in skin cancer cases. The Food and Drug Administration (FDA) lists tanning beds as possible health hazards, and the FDA and the Centers for Disease Control (CDC) encourage people to avoid using tanning and sun lamps since they contribute to eye problems such as conjunctivitis and corneal infections. Ultraviolet rays can cause serious damage to the cornea and retina. Even the American Medical Association (AMA) and the American Academy of Dermatology (AAD) are fighting to ban the use of tanning equipment for non-medical purposes.

And Yet People Still Tan…

All the facts pile up to one conclusion. THERE IS NO SAFE TAN but a fake tan. I know brown is hot. I know it makes you feel sexy and healthy. But I am through talking. Talking doesn’t seem to be helping since skin cancer due to unprotected exposure is on the rise. So I am going to leave you with a look of your sexy future if you keep tanning.

Resources

CancerWise May 2002

A Healthy Glow? The Dangers of Tanning Salons by By Michael Woo-Ming M.D., MPH

Sun damage: The true price of tanning published by The Mayo Clinic

Do Tanning Beds Cause Skin Cancer and Other Harmful Effects? by Elizabeth Carruth

Abstracts for Saturday meetings 7 OCTOBER 2000 : SUN AND SKIN – THE HEALTH AND METEOROLOGY OF ULTRAVIOLET RADIATION

Miller, S.A., Hamilton, S.L., Wester, U.G., & Cyr, W.H. (1998). An analysis of UVA emissions from sunlamps and the potential importance for melanoma. Photochemistry and Photobiology; 68(1): 63-70. (abstract).

Swerdlow, A.J. & Weinstock, M.A. (1998). Do tanning lamps cause melanoma?. Journal of the American Academy of Dermatology; 38(1): 89-98. (abstract).

DeMarini, D.M., Shelton, M.L., & Stankowski, L.F. (1995). Mutation spectra in Salmonella of sunlight, white fluorescent light, and light from tanning salon beds: induction of tandem mutations and role of DNA rapair. Mutation Research. 327(1-2): 131-149. (abstract).

Cress, R.D., Holly, E.A., & Ahn, D.K. (1995). Cutaneous melanoma in women. V. Characteristics of those who tan and those who burn when exposed to summer sun. Epidemiology; 6(5): 538-543. (abstract).

Woollons, A., Clingen, P.H., Price, M.L., Arlett, C.F., Green, M.H.L. (1997). Induction of mutagenic DNA damage in human fibroblasts after exposure to artificial tanning lamps. British Journal of Dermatology 1997; 137: 687-692.

Devgun, M.S., Johnson, B.E., & Paterson, C.R. (1981). Tanning, protection against sunburn and vitamin D formation with a UV-A ‘sun-bed.’ British Journal of Dermatology 1982; 107: 275-284.

Kennedy, M., Kim, K., Harten, B., Brown, J., Planck, S., Meshul, C.,Edelhauser, H., Rosenbaum, J.T., Armstrong, C.A., & Ansel, J.C. (1997). Ultraviolet Irradiation Induces the Production of Multiple Cytokines by Human Corneal Cells. Investigative Ophthalmology and Visual Science. Sept, 1997, Vol. 3, No. 10.

Thank you all for being so kind and understanding about the lack of blogs. With the server move for this website, bronchitis, and the move to my new, larger, location I’ve been remiss with my writing. But we are all back on track and blogs will be appearing.

I get a LOT of trade magazines – and I get behind in reading them, but I was recently laid up with a bad bout of Bronchitis and had the chance to catch up. And there I was in Skin Inc’s December 2006 issue! That’s me in the purple jacket on the left hand side sitting at a Medical Esthetic Conference in San Fransisco. …I look funny from the back!

I was sent this link and am going to let it to my job this week.
Origianl NYTimes article: Always Revealing , Human Skin Is an Anthropologist’s Map

In an era of academic hyper-specialization, Dr. Nina G. Jablonski has an amazingly broad résumé. At 53, she heads the anthropology department at Pennsylvania State University. She’s also a primatologist, an evolutionary biologist and a paleontologist.

Jeff Swensen for The New York Times
Skin tells a story of human history, says Nina G. Jablonski, an evolutionary biologist.

Last year, Dr. Jablonski led an expedition to China, where she dug for human fossils in an attempt to learn how early man coped with climate change. This month, she’s in Kenya, where she and Meave Leakey are putting together a study on prehistoric monkeys.

For more than a decade, Dr. Jablonski has been trying to get her arms around a ubiquitous and yet mysterious topic: the biology, evolution and social function of human skin. The results of her studies have been published by the University of California Press as “Skin: A Natural History.”

“Skin has been studied to absolute death by dermatologists,” Dr. Jablonski said jokingly during a recent visit to New York City. “They know it inside and out from the point of view of diseases that afflict it. What we wanted to learn was how human skin came to be as it is and what that meant for humanity.”

Q. What set you off on writing a natural history of human skin?
A. I had an insight in 1981, when I was teaching gross anatomy to medical students at the University of Hong Kong. The students had been presented with a cadaver to dissect, and they were tremendously frightened of it. However, their attitude changed the very moment they cut through the skin. With the skin gone, they began seeing it as a mere body devoid of a personal history, and they could get on with their work.

That moment showed me how much of what we consider our humanity is imbued in our skin. It stayed with me for a long time. Then about 15 years ago, I joined a project studying the natural history of skin color. The topic was so engrossing that I began looking into the larger question of what our skin does and is.

Q. And what have you found?
A. That skin is the most underappreciated of our organs. Unless we’re having the sort of problem that brings us to a dermatologist, we take our skin for granted. We never think of it as working very hard for our body or doing valuable things for us socially.

But when you really start thinking about it, it’s a factory that produces vitamin D, sweat, hormones, oils, wax, pigments – substances we need. Skin is a raincoat in that it protects us from water, bugs and noxious chemicals. It’s also a billboard which we adorn with powder, tattoos, piercing and scars to give off instant messages about our history, health, values and availability for mating.

On an evolutionary level, there are three remarkable facts about skin. It comes in colors, of course. Compared to other mammals, our skin is relatively hairless. And it’s sweaty. In the last few million years, humans became the sweatiest of mammals.

Q. Is that important?
A. Absolutely. It’s often said that our large brains are what made it possible for us to evolve from ape to human. But those big brains could never have developed if we didn’t have exceptionally sweaty skin.

It happened this way. There was a tremendous takeoff in human evolution about two million years ago when primates who could no longer be called apes appeared in the savannahs of East Africa. These early humans ran long distances in open areas. In order to survive in the equatorial sun, they needed to cool their brains. Early humans evolved an increased number of sweat glands for that purpose, which in turn permitted their brain size to expand. As soon as we developed larger brains, our planning capacity increased, and this allowed people to disperse out of Africa. There’s fossil evidence of humans appearing in Central Asia around this time.

Q. In a nutshell, what has your research shown about why humans have varying skin colors?
A. That it’s not about race – it’s about sun and about how close our ancestors lived to the Equator. Skin color is what regulates our body’s reaction to the sun and its rays. Dark skin evolved to protect the body from excessive sun rays. Light skin evolved when people migrated away from the Equator and needed to make vitamin D in their skin. To do that, they had to lose pigment. Repeatedly over history, many people moved dark to light and light to dark. That shows that color is not a permanent trait.

Q. Did early humans decorate their skin?
A. We don’t know. There’s no human skin in the fossil record. The oldest preserved skin we have is that of Ötzi, the Neolithic iceman whose mummified body was found in the Alps in 1991. Ötzi lived about 5,000 years ago. Interestingly, he has tattoos. But we can only guess what they mean.

Modern humans, we love to alter our skin. You’ll find very few people walking around today with unadorned skin. They might make permanent changes – piercing, scarring, tattooing – to memorialize events and announce their identity. Or they might use cosmetics for temporary alterations to announce their attractiveness, mood or sexual availability. The bottom line: humans are the self-decorating ape.

Q. I get the feeling that you think cosmetic use is some kind of ancient evolutionary behavior. Are we reading you correctly?

A. Evolution is all about attracting a mate and getting a chance to reproduce, so yes, makeup helps with that. When a woman uses eyeliner to make her eyes appear larger, she’s giving off a message: “I want you to see me as attractive.” Large eyes in a woman are almost universally seen as appealing. This is not just a girl thing. Male body paint in East Africa emphasizes forbidding facial expressions. They announce a man’s prowess as a warrior and as a mate.

Q. How do you feel about your own skin?
A. I like it. It is my unwritten biography. My skin reminds me that I’m a 53-year-old woman who has smiled and furrowed her brow and, on occasion, worked in the desert sun too long. I enjoy watching my skin change because it’s one of the few parts of my body that I can watch. We can’t view our livers or heart, but this we can. And yes, I use cosmetics. Like other humans, I have a penchant for changing my appearance easily and quickly. It also helps me feel more confident. That may seem silly, but I still do it.

Q. You made news in 2004 when you discovered the world’s oldest chimpanzee fossil. These were chimp teeth about a half-million years old. Where did you find them?
A. In a drawer at the National Museum of Kenya in Nairobi. I was rummaging through this bag labeled “fossil monkeys” and I saw it. “This doesn’t look like monkey,” I thought. It turned out they were from an early chimp. That find proved important because there had been no chimpanzee this old in the fossil record. By analyzing it, we’ve learned that chimpanzees in their current form have probably existed for longer than previously thought. (Laughs) Since my find, people have been rummaging through dusty museum drawers everywhere!