Mother Nature’s Kama Sutra, Part 2

KSBlogImage2Female worker bees find their food in the nectar of flowering plants. I see them flitting flower to flower sucking zealously. Most flowers have both male and female elements, leading us to think they can fertilize themselves. Mother Nature, however, blocked that mechanism in many specimens by superimposing a complicated incompatibility system to prevent the male pollen from getting to the female ovary. The only way these plants can complete the sexual act is by cross-fertilization following the matching rules of coupling between molecules with the required characteristics. The bottom line? Such plants cannot self-fertilize but can successfully fertilize most other members of the species, thus achieving outbreeding with a mix of genomes in successive generations.

Gregor Mendel, the father of inheritance—bee keeper, gardener, and monk—wanted to know how discernable traits are passed on from one generation to the next. Fortuitously, he first chose peas rather than bees for study. He cross-bred, by taking pollen from one known parent and depositing it on the tip of the tube leading to the bulbous female ovary of another. By scoring expression of certain parental traits, such as flower color and peapod shape, in the offspring of these crosses, he showed that defined characteristics of each parent were passed on from one generation to the next. Mendel tried working with bees for comparable studies. Alas the data from bees did not jibe with those of peas, due to the then unknown, unorthodox ways of sexual reproduction in bees.

Filled with the fragrance of pretty spring flowers, I turn again to that lily-padded frog pond and think of smaller creatures hidden therein—the microscopic fungi and algae. I pause to ponder the possible presence of tiny swimming spores coming from a little fresh water mold called Achlya ambisexualis, the subject of my master’s thesis many years ago. I and my mentor, John (Red) Raper fell in love while sampling small ponds in the hinterlands around Chicago to make collections of this wee critter for study back in the lab. We nurtured the spores on freshly cut hemp seeds and watched them develop into full-grown colonies of threadlike cells called hyphae. We paired the grownup colonies to look for evidence of mating.

Achlya ambisexualis is aptly named. It goes frogs, birds, fish, bees, and peas one better. It can be either male or female depending upon the partner it happens to meet. A supreme opportunist, this little mold spends no energy making fertilizing organs before they are needed. If you were one of its members, you could go either way depending upon the relative sexuality of the nearest possible partner. You could behave as male if your neighbor bears stronger female tendencies than you and vice versa.

Let’s say your male potential is stronger than that of your neighbor. She behaves as female and initiates the dalliance by sending you a signal to develop long finger-like appendages in readiness for genomic delivery. Then, and only then, do you release a message in response, telling that female to make her little nucleated egg sacks in order to receive your nuclei. She, in turn, signals your fertilizing elements hither to deliver your genes to hers within the encapsulated eggs. Voila!

My thesis aimed towards concentrating enough of a strong female’s message to determine its nature. I failed in this, but others succeeded by using better, more modern techniques. Amazingly, these later investigators defined the attracting signals of both sexes as two different steroid molecules resembling human sex hormones. The regulating genes remain unknown.

My love of the fungi persists from that time.

Moving on to the fringe of the woods, I  spot a light brown, dome-shaped mushroom hanging from a white birch tree. It must be Polyporus betulinus, a fungus studied by friend Abe Flexer, a fellow researcher in Red Raper’s lab. Abe discovered its sex life and found two sexes back in the nineteen seventies, but later investigators found more—as many as 33. How can that be?

KSBlogImage1Walking further, with mushrooms on my mind, I find a group of fan-shaped forms anchored to a log half-rotted. I kneel up close and cock my head. Each resembles a scallop shell, small as a fingernail, with irregular ridges of spore-bearing gills scoring the concave underside. It is Schizophyllum commune, my favorite mushroom-bearing fungus, with not just three dozen sexes but thousands.

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Mother Nature’s Kama Sutra, Part 1

birdBirds do it. bees do it. frogs, plants, fungi do it. Most living creatures have sex.

Why do they do that?

Sexual reproduction grabs the fastest path to long-term survival in an ever changing world. It takes energy, but going through that tangled process of mixing genetic material  from one generation to the next is worth the effort. It is the most efficient way to make a mixed array of DNA blueprints for facing life’s uncertainties. It also accelerates repair of damaged DNA which can range as high as twenty to sixty thousand injuries per day in mammalian cells such as ours.

This much I’ve learned from a life-long interest in biology focused on genetics.

But how is reproduction by means of sex accomplished?

These thoughts ran through my mind as I wandered through a Vermont woodland one fine spring day.

We humans know something of how sex works for us to spawn the next generation—basically, XX chromosomes for females versus XY chromosomes for males, with the accompanying paraphernalia. Male and female allure one another through sight, smell, taste, sound, and feel. Full attraction attained, male inserts penis into female vagina and delivers its genome packaged in sperm to join female genome in egg. Gender identity does not always match anatomical male-female differences. Same-sex allurement happens but cannot lead to procreation—we cannot reproduce our entire being by cloning, not naturally.

But ours is not the only way. What of nature’s other creatures?

frogsWalking by a lily-padded pond, I saw a tiny speckled frog perched atop a floating log. What’s with frogs? How do they strategize sex? I’ve heard their nighttime courtship calls. I  know they hatch as tadpoles from fertilized eggs in water and develop from tadpoles to full grown adults. But unlike mammals, frogs can have different kinds of sex chromosomes: some species have XX females and XY males, others have more homologous chromosomes called ZW and ZZ, and some of these little hoppers, such as the African reed frog, can defy the differential chromosome rule by switching sex when timely. Confronted with a shortage of males, females can turn into males and redress the balance. If need be, males can switch the other way around. Their sex chromosomes combine both male and female potential. Such frogs are born with both ovarian and testicular tissue, but only one type develops to function at any one time. No one yet knows just how these changes are perpetrated, but some kind of long distance signaling is probably involved.

Some fish do likewise, just to balance the sexes.

Look up to the sky, the birds up there. They have two sexes, but, unlike mammals, it’s the female who carries two different sex chromosomes (ZW) while the male has identical ones (ZZ). Through fertilization, genetic union, and the special two-step process of genetic recombination called meiosis, female determines the sexual identity of offspring.

beesBees bustle within the fragrance of spring flowers. For these busy little buzzers, only females develop from eggs fertilized by sperm. Males, oddly enough, develop from unfertilized eggs that are derived either from the queen bee or from a rather rare so-called laying worker bee. Thus, a male genome, with just one set of chromosomes coming from a  female egg, is half the value of a new born female with two sets of chromosomes, one from the female parent plus one from the male parent. The doubly endowed females go out and work for a living; the males are drones who can’t even sting or forage. Being fed by worker females, a drone’s purpose in life is to fertilize some of the queen’s eggs—whereupon he expires in the act, leaving part of his innards behind. Usually a hive generates just one queen by nurturing a selected female with a special diet of royal jelly the first two weeks of life. This special feeding, denied to ordinary workers, is necessary for female organ development.

Working female bees gather food for the colony. They are the ones who sting. I wonder why, since death ensues thereafter. Perhaps it is a sacrificial act in protection of the hive. Alas, those female workers produce only male offspring. It is the queen of the lot who makes more females. She must stay healthy to keep the whole colony replenished with a proper gender balance.

My brother kept bees. Sometimes the queen escaped its hive leading the colony elsewhere. If those renegades settled on a tractable bush nearby, I’d cover up in overalls, netted hat and gloves, give that bush a shaking, dislodge them all into a wide-mouth container, close the lid, then carry them back to my brother’s hive for the fee of fifty cents. I did not get stung, nor did I ever earn much.

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*Excerpt from an essay published in The Best of  the Burlington Writers Workshop, 2016

All Animals Care

sea lion pup

Dogs, cats, even rats, can bond with human animals and come to care about us. But what about the wild ones?

While recently watching naturalist Joe Hutto, on Public Television’s Nature program, commune with wild mule deer, I thought of the time I sat alone on a volcanic island of the Galapagos as little lizards, Marine Iguanas, scurried linearly close by, and walloping sea lions stopped to lick my toes. It all seemed like a friendly greeting.

Joe Hutto spent a couple of years relating to a herd of mule deer on his land in the Wind River Region of Wyoming, and those deer came to trust him, even care for him. The head of the herd, he named Ragtag, cared so much she even licked his cheek in tenderness. When Ragtag died the whole herd visibly mourned. I was moved to tears when Joe Hutto found Ragtag’s orphaned faun, Molly, lying helplessly hungry without her mother. He nursed her to maturity and she became his constant friend.

Then I thought of a mother sea lion on the beach of another Galapagos Island who had just given birth to a still-born pup. That mother licked her baby for several minutes trying to restore life—to no avail. She then spent all her energy nudging that inert babe to the ocean’s edge and let it float out to the sea. No member of her herd came to offer condolences, even those nearby. None even came by out of curiosity, except a yearling offspring of that sad mother, who stood by and stared and stared.

Growing Old Gracefully

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I had five older brothers and four sisters-in-law. They’re all gone, dead, passed on, recycled—save one: my younger brother’s wife, Grace. Grace is one hundred going on one-oh-one. She can’t see; can’t walk, can’t hear very well, but Grace is lucid, sweet, smart, and beloved. She’s grown old gracefully, just as my mother said we should all try to do. Grace has 10 years, 8 months, 18 days on me. I can see, smell, taste, walk, even play tennis, but—thinking of Grace—can’t help contemplate my future. Will I, can I, grow old gracefully?

But I shall not think anymore about that today. Instead, I will make myself a sinful breakfast of bacon and buttered waffles amply laced with Vermont maple syrup; I shall read the newspaper; the New Yorker—maybe finish Archer Mayor’s Paradise City—take a walk; watch a bit of the Australian Open and, after that, catch the NFL playoffs.

I will postpone working on my book, “Tobacco Farm Tales,” until tomorrow. Today, I shall not think any more about growing old gracefully.

Science and the Law

After spending a couple days with a large group of lawyers as keynote speaker at their annual “Winter Melt” in Montreal last weekend, I recalled a childhood revelation about the difference between science and the law.

My dad was a lawyer, but I wanted to be a scientist and discover the balanced truth about some unknown phenomenon. Even in third grade, I knew that scientists start with an idea, do experiments to get information about it, make observations, and try to maintain an unbiased view of what the discovered facts say. Well, Dad came home from the office one day and went on and on about how he had to appear in court and advocate for his client. It seemed to me, he was cherry picking facts in order to make the best case scenario on behalf of that client. I said to him, “But Dad, you’re not looking at all sides; you’re not trying to find the truth!” He replied, “I know, but that’s the way of the law. It’s better than neighbors trying to settle their disputes by hitting each other over the head with an axe!”

Well, I’m glad I did grow up to be a scientist instead of a lawyer, but my respect for lawyers and what they do expanded significantly last weekend. Those lawyers attending the Vermont Bar Association’s “Winter Melt” seemed smart as whips and harbored much curiosity about all sorts of things—even my talk about the importance of fungi and all the different ways they accomplish sexual reproduction.

Long Life as Scientist, Mother and Writer, Now 88 and Proud of it!

Cardy wanting to be a boy.

Cardy wanting to be a boy.

Starting as student, becoming scientist, wife/parent, then science again, I’m into my final career as writer and promoter of writing (www.cardyraper.com). My memoir titled A Woman of Science: An Extraordinary Journey of Love, Discovery, and the Sex Life of Mushrooms, will be published by Hatherleigh Press, distributed by Random House, on May 28th this year.

I think it is time to start blogging. So here I am, planning to post periodic thoughts hopefully worth mentioning.
For starters, I was asked in a recent radio interview whether or not I believe in God. Wow, how to answer that question when talking to unseen strangers of various faiths! Well, I can’t quite remember just how I answered without checking back to the podcast (www.barryshainbaum.com/radio.html, March 3 show) but it went something like this: Although brought up believing in an all powerful, all knowing, personified God who sits in judgement of all on earth, that concept no longer fits my thinking. I just don’t know how or why I am here on this planet within a universe that started with one big bang. I just don’t know where that big bang came from to begin with. It simply doesn’t help me to think of it as God’s doing, because then I must ask what begets God. I think of God as an unknown force, probably never to be truly known by the likes of us.
I don’t even know why I started this blog with such heady thoughts, except for that interview yesterday.
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