Coral Hybrid: Sex Gone Awry or Saving Grace?

 

Spawning Acropora palmata

Elkhorn coral spawning. Photo credit: Mark Vermeij

 

 

 

 

 

 

 

 

 

Excited to have my second Guest Blog on Scientific American about a favorite subject: coral mass spawning. Huge thanks to Dr. Nicole Fogarty at Nova Southeastern University for sharing her stories and Dr. Mark Vermeij at CARMABI for fantastic images.

Lolita of the Sea(weed): Update

******So complex and utterly alien are the sex lives of seaweeds that my original blog post on the subject from April required some updating. With much thanks to Dr. Chopin for editing assistance, here’s a revisit to the scandalous sex life of a seaweed. ******

Lolita, By Vladimir Nabokov

Vladimir Nabokov’s Lolita

Lo-lee-ta: the tip of the tongue taking a trip of three steps down the palate to tap, at three, on the teeth. Lo. Lee. Ta.

One of the greatest opening lines of all time, this is the introduction to Vladimir Nabokov’s brilliant and disturbing Lolita. A long-held favorite of mine, I was utterly thrilled when seaweed guru Dr. Thierry Chopin referred to this modern classic as a model for understanding the complex and rather shocking sex life of a common edible seaweed.

I know what you may be thinking: seaweeds have sex lives?

Dulse along Canada's eastern rocky shore

The red seaweed called dulse and sugar kelp, a brown seaweed, seen in abundance at low tide along the rocky shore of the Bay of Fundy, New Brunswick, Canada (photo credit: Thierry Chopin)

Yes. Don’t let those passively swaying fronds fool you. Despite their rather limp appearance, seaweeds (also commonly known as marine macroalgae) are raging sex machines, with some of the strangest and most creative forms of sexual reproduction on the planet.  A catch-all group that lumps together remarkably diverse species (green seaweeds are more closely related to trees than they are to brown seaweeds, for example, which are more closely related to fungi), it is no surprise that they display an enormous range of reproductive strategies. Chopin wrote a debrief here on seaweed sex after our interview for Sex in the Sea; he’s insisting that I must include a chapter (or two!) on seaweed reproduction, and I heartily agree. Here’s why: seaweed cultivation is big.  Globally, seaweed farmers grow 23.8 million tonnes a year—nearly 50% of all the world’s ocean farming worth $US 6.4 billion.
Large scale seaweed (kelp) cultivation in Sungo Bay, China. Note seaweeds grown integrated with the cultivation of several invertebrate species (oysters, scallops, abalones and sea cucumbers) (photo credit: Thierry Chopin).

Large scale seaweed (kelp) cultivation in Sungo Bay, China. Note seaweeds grown integrated with the cultivation of several invertebrate species (oysters, scallops, abalones and sea cucumbers) (photo credit: Thierry Chopin).

Long recognized as a healthy and delicious food in Asia, seaweed farming is gaining traction in the west, including in Canada, Chile, Europe, and the USA. And it’s not just food that seaweed bestows; this video provides a great overview of the varied and everyday uses for seaweed.

Fast growing and photosynthetic, seaweeds don’t need to be fed like fish or shrimp; they just need sunlight and nutrient rich waters (which they help keep clean) to grow.  They are being tested as natural ways to clean up effluent from fish farms (a key focus of Chopin’s work on Integrated Multi-Trophic Aquaculture), mitigate climate change, and produce healthy and abundant food.  But in order for us to grow more seaweeds, we’ve got to know how they reproduce. We need to understand in intimate detail, the intimate acts of seaweed.

Talking with Chopin, it is clear that there is no one “sex life” of seaweeds. Instead, there is an endless fractal-like sexscape with every imaginable permutation: male-female couplings? They got that. Hermaphrodites? Sure. Asexual inter-generational phases? Check. Dwarf females? Yup. Self-perpetuating parthenogenetic gametes alternating with asexual spore germination…they’ve got that too. And, they can also claim, according to Chopin, “old male perverts” and temptress nymphets.  Which brings us back to Lolita.

cocktails from seaweed

Kelp cocktails, brain child of Bren Smith at Thimble Island Oysters and talented chefs across New York City (photo credit: drinkinginamerica.com)

Deciphering the wild life cycles of these remarkable food factories has challenged many a phycologist (note: that’s not a typo for a shrink, but a scientist who studies algae). But, with the help of Chopin’s expertise and anything-but-prude French perspective (and a few kelp cocktails), I’m slowly wrapping my nori around it all. Here, for your summer reading pleasure, is the tantalizing tale of a seaweed named dulse (Palmaria palmata) though “Dolores” would be more appropriate.  May your innocent strolls along the seaside never be quite the same again.

An innocent stroll along the seaside (photo credit: windydress via Flickr)

An innocent stroll along the seaside (photo credit: windydress via Flickr)

It all starts with the females, who, according to Chopin, are all young and extremely sexually precocious (seaweeds, like many plants, can have separate sexes, with individuals maturing as males or females). At just a few weeks old, female dulse have fully mature sexual organs called trichogynes  which are slender tubes that reach out to receive the male gametes.

Microscopic mature female gametophyte (left) of the red seaweed Palmaria palmata (dulse) with trichogyne filament visible on the left. On the upper right, a young male gametophyte just starting to elongate. The scale bar at the bottom right represents 0.1 mm (photo credit: Constanza Chianale).

Microscopic mature female gametophyte (left) of the red seaweed Palmaria palmata (dulse) with trichogyne filament visible on the left. On the upper right, a young male gametophyte just starting to elongate. The scale bar at the bottom right represents 0.1 mm (photo credit: Constanza Chianale).

But, these blossoming beauties (what Chopin refers to as the “Lolitas”) are also microscopic in size, a tiny disc less than a millimeter in diameter. For decades scientists searched for the mature females in vain, only discovering them through some accidental lab experiments in the 1980s. The much larger mature males were more easily spotted in the field (but specialists in the lab still had to confirm identification), while the females remained a mystery, their small size but one contributing factor…

…the other reason was that they were rapidly buried alive by their own offspring. But, we’ll get to that.

First, it’s important to note that male dulse, like in some other species we know, don’t grow-up quite as quickly as their female counterparts. In fact, males the same age as mature females are but young, pre-pubescent boys, incapable of satisfying the females’ desires. Males of the previous generation, however, don’t have this problem. Having weathered a winter, so to speak, these older males are more than capable of giving the females what they want: a shower of seed. These older males readily release their tail-less, sperm-like spermatia into the water, relying on the currents to whisk them atop the thin crust of the female. If just one lucky spermatium makes contact with a female’s trichogyne, fertilization can progress.

dulse life cycle

A general life cycle of dulse, adapted from van der Meer J.P. and Todd E.R. 1980. The life history of Palmaria palmata in culture. A new type for the Rhodophyta. Canadian Journal of Botany 58:1250-1256

But the product of this union is rather unusual.  As Chopin explained it in Lolita terms: “So, say a female dulse, Dolores, receives a spermatium from an older male dulse, Humbert. When this happens, the fertilized egg develops into what looks like a mini Humbert, but is actually an asexual sporophyte that starts to sprout from Dolores’ thin surface.”

Let’s call that sporophyte, Pat. Unlike Dolores and Humbert, which are gametophytes—the gamete-producing part of the seaweed’s life cycle—Pat produces asexual spores. As it develops, Pat overgrows the dwarf female Dolores from which it sprang, swallowing her up as if she never existed. That’s really why scientists couldn’t find the mature females of the dulse world: they were overgrown by their offspring’s sporophyte fronds.

Mature sporophyte of the red seaweed Palmaria palmata (dulse), with darker sori of spores (thousands grouped in quadruplets) (photo credit: Thierry Chopin)

Mature sporophyte of the red seaweed Palmaria palmata (dulse), with darker sori of spores (thousands grouped in quadruplets) (photo credit: Thierry Chopin)

Once Dolores is squashed, Pat, having reached a large size, then produces many sets of quadruplet spores, grouped by the thousands to form dark spots, called sori (these dark spots make this the easiest stage of the life cycle to recognize). Every quadruplet has two spores that develop into boys and two that become girls. And these are the gametophytes that can sexually reproduce again.
But the girls can reproduce far sooner. They, like the overgrown Dolores, are nymphets, reaching sexual maturity within a few weeks. As Chopin puts it “and the boys being boys, the girls have to court the males from the older generation. Thus, it is generations after generations. And that’s where things get all Nabokov.”
So, the cycle of inter-generational coupling continues, as these new Lolitas court the males of Dolores’ generation, who are finally sexually mature (eight to twelve months later). Within the same generation, there is no way for one of these nubile females to mate with a guy her own age (of course, this also means she can’t mate with her brothers, which could be why the dulse does it this way).

Chopin concludes: Precocious sexuality of little Palmaria females with their mother’s male siblings, who have finally reached maturity, condemns them to being buried by their offspring’s overgrowing holdfast on the same rocky spot they occupy, hence leading people to believe for a very long time that they never existed!  

It’s a female-mates-with-mother’s-brother-bares-asexual-offspring-that-smothers-mother world out there for dulse.  Figuring out this convoluted life cycle was an important step forward in our ability to cultivate this popular food—and learn how other seaweeds might be doing it.

Of course, there’s another bonus to understanding seaweed sex, besides the opportunities for food production, ecosystem restoration, and other advantages: whatever drives their sex could help our own sex drive, too. Something to consider next time you crunch through that sushi roll.

Getting to Know Whale Vaginas in Seven Steps

Whale underside

Getting a glimpse at a whale’s undercarriage. Photo by Richard Fisher.

Thrilled to announce that I have my first guest blog featured on Scientific American blogs. Check out the full post there.

A teaser:

Step 1: Leverage Victorians’ obsessions with sea creatures

Step 2: Ask a stranger to FedEx a Whale Vagina…

FedEx Mailbox

When you’re mailing a whale vagina, you can trust FedEx

A huge thanks to Dr. Sarah Mesnick with the Southwest Fisheries Science Center, NOAA and Scripps Institution of Oceanography (and a great mentor of mine) for the fantastic interview that inspired this post. More to come about Dr. Mesnick’s work and marine mammal sex soon. Stay tuned!

Salty Sex Hightlights: April

Photo: Newitz blog title

Every month you can check in here to find the highlights from some salty sex stories from the science and pop culture worlds. During April, I focused on species that have some flex with their sex, as you can tell from the previous post.   As with any journey, there were many side excursions along the way (see #6 below). A more complete collection of articles that caught my attention are at my Sex In The Sea Flipboard magazine, but here’s some top finds from this month’s dive into the red light districts of the big blue:

1. Bluebanded gobies (Lythrypnus dalli): sex change champions of the vertebrate world, fins down. These shy little fish hold nothing back when it comes to performing some serious gender benders: females can morph to males, males back to females, and then back to male again, if the social situation demands it. Flexible with their sexual state, they don’t bend the rules on when to swap: if subordinate, be female; when in doubt, wait it out.  The latter rule means that a goby, placed into a confusing social situation, unsure where they fall in the ranks, will simply revert back to “vanilla” as Dr. Matthew Grober explains it. Their gonads and genitalia become ambiguous. In this fish, peer pressure can make you king of the castle, humble harem-mate, or, Pat.

Photo: bluebanded goby

Bluebanded goby hiding under a sea urchin. Photo credit: Peter Liu

2. INTRODUCING THE GYNOSOME!!! Scientists discovered a new sex organ on the planet “that challenges everything we knew about sexual selection.” It’s called the gynosome, and it’s found in a rare cave insect in the genius Neotrolga.  Not marine, but worth the mention because it is so, well, awesome.  The gynosome belongs to the female Neotrolga, who can use it to penetrate the male in order to receive sperm and very likely nutrition. These randy bugs get it on for sexual bouts that can last up to 70 hours.  To keep everything in place for these marathon sex sessions, spines along the gynosome slot into specific pounches in the male’s reproductive chamber. Like a lock and key, each species has its own configuration. The locking mechansim ensures that even when a researcher comes to pry a copulating couple apart, the  head and torso of the male will break off before the gynosome will give way. Now there’s a need for conscious uncoupling.  For a fantastic run down of how this works, check out Jason Goldman’s article.  Can’t wait to see Isabella Rosselini’s costume for this one…

Photo: Isabella Rosselini as a lusty bee

Isabella Rossilini as a horny insect in Green Porno

3. While scientists were discovering a new sex organ, science journalists were figuring out how to talk about it. The take home: when naming a new body part, don’t call it what it’s not.

Photo: Newitz blog title

Newitz on why calling the gynosome a penis makes us a little less smart

 

If you read the coverage of Neotrolga’s discovery in the mainstream media, you’re likely to walk away with the terms “female penis” or “penis-like appendage” in your brain. Afterall, the original research paper used the latter term in the abstract. But, as io9 editor Annalee Newitz notes in her article “Your Penis is Getting the Way of My Science,” this remarkable new discovery was not of a penis, nor a penis-like organ at all.  It was a gynosome, a totally new, totally different kind of sex organ: as stated in #2, it’s an inflatable female receptacle (not a delivery device) that penetrates the male’s sex chamber, enlarges, and locks into place in order to receive “voluminous” amounts of sperm that likely nourish the female as much as they knock her up (for several species, ejaculate is like a protein shake that can get you pregnant).  Given such remarkable and unusual attributes, the gynosome deserves recognition for what it is, a truly novel biological structure. To call it a “penis-like” anything is a disservice to science and to us. As Newitz writes:

“When we deprive Neotrogla of her gynosome by calling it a penis, of courseNeotrogla doesn’t care. But we fail to advance the scientific project, which is above all things dedicated to expanding people’s understanding of the world. Instead of learning that there are female bugs with sex organs that behave unlike anything in the human world, articles about a “female penis” reassure readers that nothing could ever exist that challenges the penis/vagina sexual system — nor the system of sexual selection that led to it. And that makes our minds a little smaller.”

Photo: Young article on gynosome

Young, reporting on the gynosome discovery

I can’t blame the scientists for using the term “penis-like” in their description- afterall, the average entomology paper isn’t typically splashed all over major media outlets.  Simplifying the discovery to something that sounded familiar, yet strange, was a great strategy (whether intentional or not) to draw attention to their research (though, new sex organs are probably novel enough to not need a penis joke to get some attention).  But the role of the science journalism world is to take science and turn it into stories that open up further understanding, not shove ideas and revelations into boxes that just don’t fit. We’ve got to be able to build a new, er, box.  The conversation sparked interesting commentary from some great science bloggers including Ed Young over at Not Exactly Rocket Science, along with Jason Goldman, back at io9.  In the end, I think Jason’s argument, drawing from the falls of the once- mighty Pluto and brontosaurus, provides the best rationale for why it matters that we lose the “female penis” analogy.

4. “Finding Nemo lied to your kids, and will do it again in the sequel: finding Dory.”

Photo: clownfish in anemone

Clownfish, more like Oedipus than Nemo. Source.

Sorry Nemo fans, but the truth is out: by the time Nemo dropped into that aquarium tank, his dad Marlin would have morphed into Marlene.  The folks over at The Fisheries Blog summed it up. Check them out for excellent breakdown of pop culture as it relates to fisheries.

5. Color-coded sex change and reverse ejaculation: the ribbon eel (Rhinomuraena quaesita). As young juveniles, these elongate fish are black with a bright yellow stripe along their backs.  Puberty turns the black to blue as the fish develops fully functioning male parts.  A few years later, the blue fades and the whole body turns bright yellow as they change from male to female (protandry).  And here’s a fun fact (besides the colorful sex change): this eel is the only vertebrate known to have its gonads in its tail, located past the anus. This means it has to ejaculate towards—rather than away—from its head.  Good thing they’re so long…keeps ‘em from squirting sperm in their eyes.

Photo: juvenile ribbon eel.

Juvenile ribbon eel () (Source)

Photo: adult male ribbon eel

Adult male ribbon eel (Source)

Photo: ribbon eel female

Female ribbon eel (Source)

6. Finally, we get to sea otters, which do not change sex but do some other rather freaky stuff.  Here’s a disturbing yet true tale of the dark side of sea otters.  If you like these furry, cute little elementary backstrokers with a penchant for abalone, do *not* click that link—author Mathhews holds nothing back in his case again these “necrophiliac, serial-killing fur monsters of the sea.”

This piece makes me think I need to reconsider the subtitle for the book:

Sex in the sea—just cuz it’s in water, don’t mean it’s clean.  What do you think?

As always, comments, contributions, and musings are welcome.  If you are conducting research on an animal that swaps sex, let me know.  Stay tuned for more on this subject…oysters anyone?

Sex Change By the Numbers: a tax season reflection

Getting the arithmetic right matters more than you may think for fish...

Getting the arithmetic right matters more than you may think for fish…

While we’ve all been busy crunching numbers for tax time, the female bucktooth parrotfish has been doing a little math, too—except instead of calculating taxes, she’s deciding whether or not to change sex.  In the world of fish, getting the arithmetic right can make or break your sex life.

Fish are some of the few vertebrates that have the ability to regularly change sex (other verts, such as some frogs, may do it under extreme circumstances). And while this is a pretty nifty party trick, changing sex takes a lot of energy- transforming one’s genitals and gonads (external and internal sex parts) is no simple task. So why do fish bother? The answer is: reproductive success. It all comes down to how many offspring an individual can produce. Here’s how it works:

The most common way fish change sex is from female to male. This is called (take a breath) sequential (one sex after another) protogynous (first female, then male) hermaphroditism (one individual, two sexes in a lifetime). In general, for species where big males can control access to females (think harem), it pays to be female when small (you get to reproduce with the dominant male) and then turn into a male when you are big enough to duke it out with a competing male to win access to a group of females.  There are also protandrous hermaphrodites, who start male and turn to female (brace yourselves, Finding Nemo fans, the folks at The Fisheries Blog don’t mince fins on this one)—more on that strategy later.

Back to why switching to male can make sense: sperm are less expensive to manufacture than eggs, so one male will be able to make lots more sperm than a similar sized female can produce eggs—as long as there are enough females churning out enough eggs for the male to fertilize, he’ll make more offspring. The female-to-male sex switching strategy allows for maximum reproduction during all stages of life, when small and when larger…if the conditions are right.

Bucktooth parrotfish. Photo credit: Kevin Bryant.

Bucktooth parrotfish. Photo credit: Kevin Bryant.

And here’s where a little math goes a long way.

Unlike us, the bigger the fish, the more eggs or sperm they can produce. For our species, every woman is born with a set number of eggs, no matter if she grows to be a towering 5’11” or petite 5’0″. And a man’s sperm count has little to do with body size.  Not so for fish. The bigger the female, the larger the number of eggs she produces (and often, the higher quality).  A fish that doubles in size may gain over 10x as many eggs. This fact alone has major implications for management: catching one large female fish can reduce the reproductive output of a school by the same amount as several smaller females. Accounting for that in setting quotas and size limits can be really complicated, but it is critical to effective management. Saving these Big Old Fat Fertile Female Fish (BOFFFS) has become a focused effort of some conservation initiatives, including design of marine protected areas.

Which takes us back to the arithmetic those bucktooth parrotfish females are constantly conducting.  As they grow larger, they have to weigh which choice will bring more babies: changing to male and gaining access to multiple females or staying female, and having your eggs fertilized by the dominant male.  If the sum total of all the eggs produced by all the other females is more than your total number of eggs, it pays to switch and be the male. But, if as a large female you make more eggs than all the other females combined, than you should stay female.

 

Photo credit: Flickr Creative Commons

Photo credit: Flickr Creative Commons

If (female 1 + female 2 + female 3) < eggs than female 4, female 4 stays female.

If (female 1 + female 2 + female 3) > eggs than female 4, female 4 will likely switch to male and take over the harem (and thus begin fertilizing all those eggs).

A large female is especially likely to skip sex change if there are other males around crashing the love nest. In some species, the dominant male is not as dominant as he looks: “sneaker” males that hide nearby can dash in and add their own sperm to the mix (remember, fish have external fertilization, casting sperm and eggs into the water) right when the dominant male spawns. These “sneakers” create high levels of sperm competition that dilute the dominant male’s success rates.  This is good for females, whose eggs are bathed by plenty o’sperm (and a greater diversity of genes), but it is bad news for the male. Studies have shown that in species where this happens, large females often choose not to turn into males. Such is the case with bucktooth parrotfish.

Instead of the standard large size/status-triggered sex change of most protogynous hermaphrodites, large female bucktooth parrotfish are constantly sizing up the other females in the harem, noting the sneakers streaking in, and doing a little mental math to figure out whether its worth it to change sex. And you thought figuring out your taxes was hard.

 

 

 

 

 

It’s Official!!!!

Book contract in the mail...

Book contract in the mail…

It is with great excitement that I can announce that Sex in the Sea has been picked up by the fantastic folks at Palgrave MacMillan. We entered discussions a few weeks ago and today I received the signed contract. With an official book deal to light a fire under me, this blog is set to house some exciting, entertaining, and far more frequent tales of wondrous ways life begets life beneath the waves—and why that matters.  Thanks for reading, be sure to subscribe, and please spread the word!

Hordes of horny horseshoe crabs likely saved you, but can you save them?

Mating Season, Lewes, Delaware  Jacqueline Bedell WOD submission

Forget the teenagers making out under the boardwalk, the real love fest at the Jersey Shore each summer happens at the water’s edge. That’s where hundreds of horny horseshoe crabs plow their helmeted heads into the shallow wedge between the surface and the sloping bottom. More closely related to scorpions and trilobites than crabs, these ancient arthropods look the same today as their ancestors did over 400 million years ago, and likely get it on much the same way their relatives did too: in gigantic orgies. Talk about a family tradition.

The males arrive first and begin patrolling the water’s edge looking for females. When spotted, they scuttle over and climb onto her back, using special hooked claws to latch on. For days or even weeks he may hang there just waiting for her to lay a batch of her 80,000 eggs. By the time she does, 5 or 6 males may have attached themselves to her (or often, to the other males gripping her shell, forming a love chain).  She’s got to drag them all over the beach as she gets ready to dig her nest and lay those eggs.  But, since she cannot choose who clings on, having multiple mates helps increase the chance of a few fit fathers getting into the mix.

Besides providing for provocative beachside entertainment, horseshoe crabs play another critical role for us humans: their blue blood provides the only defense we have against bacterial contamination in drugs and medical implants.

You read that right. It’s their remarkable fluid make-up that ensures our vaccinations are safe. And for anyone out there with a heart valve, prosthetic, or other intravenous device—horseshoe crabs have your back, too.  Compounds in their blood (and so far, only their blood seems to have it) can detect even the slightest traces of bacterial contaminant, providing the ultimate safety screening.

Their blood is so important, there are now horseshoe crab phlebotomists, experts at draining their blood and (ideally) releasing the animals back into the wild, woozy but hopefully unharmed (some studies show 10-15% mortality rates—not great for a blood bank, but the total deaths from medicinal use are still far below those from the fishery, the primary source of their demise).

Horseshoe crab blood bank.

Trouble is, there are fewer and fewer horseshoe crabs around these days. In Delaware Bay, numbers have dropped 90% in 150 years. Overfishing, mostly for their use as bait for the eel and whelk fishery, has caused dramatic declines in recent years.  But, as the demand for their blood has increased, the occasional clandestine pillage of the mating masses for their sacred sangre adds insult to injury.  Like grunion in the previous post, they also suffer from threats to their shallow love nests such as sea level rise.

Declining populations of horseshoe crabs isn’t only bad news for them and us. It’s also disastrous for migrating shorebirds, such as the endangered Red Knot. The eastern seaboard is a perfect pit stop on their 9000 mile journey from the tip of South America to their breeding grounds in the Arctic.  They rely on the millions of horseshoe crab eggs covering the beach to refuel themselves.  As horseshoe crabs plummet, so do the seabirds. It’s a system where success hinges on huge numbers of horseshoe crabs getting in on.

In other words, we all need those orgies—the horseshoe crabs, the seabirds, and us. Without successful mass mating, we’re all sunk.

Good news is, there are efforts to design new bait sources and techniques to reduce the number of horseshoe crabs tossed into traps. And efforts to make catching gravid females illegal (evidently the females with the eggs make for the choicest bait—but you can’t make more horseshoe crabs if you keep serving up the adults and their eggs to eels and snails).

So, the next time you get that flu shot and walk away feeling fine, give a nod to those ancient helmeted warriors and their bright blue blood.  And then, see if you can help bring them back. If you live on the eastern seaboard, search for “volunteer horseshoe crab” and your state to find out more.

50 Shades of Grunion Run

Grunion run along the CA coast. Photo credit: Haris Lakisic, Pepperdine.

Her skin shone silver in the moonlight, a flash against the dark beach. She knew he wanted her. She could see him struggling, desperately fighting his way toward her. She positioned herself perfectly, knowing the site of her bound body, restrained and prostrate in the sand would make him—would make of all them—quiver with excitement.  The first to reach her, he feverishly curled himself around her as the others closed in, forming their own half-circle embraces.  She strained with the effort, with the closeness of all those bodies squeezing against her, and yet, her arousal only climbed with the number of strong, sleek forms wrapping around her. 

But just when she thought she couldn’t take any more, just as the lack of oxygen began to make her head spin, she could feel their grips relax and the slow, sweet slide of their pleasure slipping down her body. Their desire to hold her vanished the moment their burden was unleashed. 

How quickly they relinquished their hold of her, turning tail and heading back into the night.  Alone, she struggled to free herself from her binds, now more treacherous than alluring.  She gasped for breath and with her last bit of energy tore free of the hold. Quickly, she too turned toward the water’s edge, catching the next wave back out to sea.  Her suitors long gone, she would never know their names, never recognize them, masked as they were by the shadow of night.  But back there on the beach, somewhere safely tucked down beneath a thousand grains of sand, their DNA mingled and mixed with her own.  Knowing this, she could swim at peace…until next month’s full moon cast it’s spell, luring her ashore once again.

And that, dear reader, is the cleaned up version.

It’s of one of the most heroic and extreme acts of sex the sea provides.  And it happens by the thousands, every year, along the southern coast of California all the way to Baja.  If you live there, right now, you may be able to catch the tail end of this event (and likely be one of the only tourists to recognize how friggin’ masochistic this behavior actually is). These sexual extremists are grunion, Spanish for “grunters”—their onomatopoeic namesake reflecting the raucous they make in their effort to reproduce on shore. Their mass beachings are  called the “grunion runs” and they happen a few days after the full moon in spring and summer.

Grunions are not alone in the category of marine life that comes ashore for sex.  Female sea turtles have to heave their heft up sandy slopes to lay their eggs and elephant seals haul out to hump it up. But as I’ve been purusing the literature about group sex in fish, thus far, these guys are the only fish I’ve found that seal the deal in the sand.  Please let me know if I am missing others.

And, true to the title of this post, the act of flinging oneself on shore isn’t all these fish do to get laid. The females take the whole suffocation fetish (fish can’t breathe while out of the water, remember) and throw a little beach-sand bondage into the mix.  Once on shore, she digs her tail into the soft sand, sinking herself deep down, up to her armpits (sometimes, a females whole head will go under).  With her head sticking straight out of the sand, she presents herself as one sexy beast. The males flap their way up slope (she is holding her breath this whole time, remember, and the girl did some digging!), circle themselves around her, and then use her side as a slide for their sperm.  Oozing all over her body, the slippery stuff makes it way down to the eggs she has deposited below.  The males then turn tail and head back to the water, leaving her to dig herself out (still holding her breath) and catch the next wave out to sea.

Why go through such effort? Why risk beach stranding? I’m still getting to the heart of the matter, but thus far, it seems as though the benefits are associated with higher fertilization rates—the result of 1) the eggs being contained in the sand and not dispersed into the big blue sea and 2) nearly direct deposit of sperm onto the eggs, something more difficult to achieve in water.

Why the group sex? Well, first, the conditions have to be right for the fish to get far enough ashore to lay the eggs and not have them washed right back out to sea, but have the eggs in the right spot to be carried back out to see once they are hatched.  The grunion have adapted to local tidal cycles exactly in order to perfect this timing. The moon cues this timing, so the whole population takes advantage at once.  Second, from the female’s perspective, by having multiple males wrap around her and deposit sperm all together, she increases the diversity of DNA that reaches her eggs. This ups the odds that among that mix of dads, there will be some really fit dudes to make up for any duds.

So, why do we need to know this? Well, for some, watching the grunion runs is quite the experience. It is a pretty spectacular visual, seeing thousands of silver shards flapping in the moonlight.  It also brings up the importance of protecting prime mating habitat. These fish depend on these beaches to support their sexual endeavors. As extreme as they are, they cannot overcome massive beach erosion due to poor land management, or disappearing beaches due to rising sea levels. For these fish, life literally is bound to beach.  To protect these kinky little silversides, and continue to watch them flaunt their stuff, requires we take action to protect the coastline they depend upon.

Check out this cool new documentary, Surf, Sand, and Silversides: The California Grunion for more info.

Stay tuned for more on oceanic orgies as I continue to research this chapter for my book! As always, comments welcomed!

The Sex Appeal of High Heels

Jessica Rabbit from Disney's Who Framed Roger Rabbit

Jessica Rabbit from Disney’s Who Framed Roger Rabbit

There is no doubt about it. High heels are sexy. But why?

It likely has nothing to do with feet and everything to do with the up-turned ass that wearing these shoes creates (see dramatic Disney renditioning of the effect to the right).  Called “lordosis”, the posture is a universal signal of sexual readiness (probably something those 17th C. aristocratic dudes didn’t realize when they first adopted the fashion of wearing heels).

Cats do it, rats do it, even elephant seals do it.  It’s just that in the animal kingdom, such a stance comes as a spontaneous, hormon-driven response to the touch of a male, as opposed to a wardrobe selection.

According to the authors of the fabulous book, Zoobiquity, here is how it works: a nerve signal triggered by a mounting (or in some cases, gently touching) male sends a message to the female brain. Depending on where the female is in her cycle, levels of sex hormones relay the message to say “assume the position” if the female is receptive or “Clock him one and get the hell outta there” if the female is not so ready.

In cats, the response is really extreme and obvious. So too in rats and horses—a female may even lift her tail out of the way to expose herself.  It’s slightly more subtle in cows and primates. And in elephant seals, it takes a keen eye to spot.

Mating Northern Elephant Seal near San Simeon, CA

Mating Northern Elephant Seal near San Simeon, CA by Mike Baird

In this species, the female rarely outwardly solicits sex from the harem master (and who can blame her? Would you want 5000 lbs of hulking seal bubbler pressing you into the shifting sands?). But closer scrutiny shows she may subtly cue that she is ready by spreading her flippers and raising her rear when he lays a flipper across her back.  It’s slight, but it is definitely lordosis.

So, gentlemen attracted to the hot brunette in the six-inch red stilettos can feel in good company with a host of other mammalian males: it is a deep-rooted, primitive evolutionary response.

 

Which makes me wonder: could we create this effect in other species, too?

Walk_a_thon by William Wegman.

In other words, if it were possible to give a little lift to the rear of a female, would an otherwise uninterested male swoop in? Could it help captive breeding programs struggling to get endangered species to mate?  What would that look like? Come on designers… chime in.

 

 

The world’s only disposable-re-growable penis-just in time for Valentine’s Day

Photo credit: xmatt

Photo credit: xmatt

Move over lizards. Re-growing a tail ain’t nothing compared to re-growing a penis—especially when it only takes 24 hours. And what strapping, brawny, stallion is man enough to un-man for a few moments and then regenerate an entirely new, functional member “all in a day’s work”?  None other than Chromodoris reticulata. It’s a sea slug, folks. And scientists yesterday just announced it is also the only known disposable-re-growable johnson on the planet.

Not only can they drop their penises, but, a back-up penis, ready for action, emerges within 24hrs.

Turns out, these slugs have a long, coiled structure that unfurls penis, after penis, after penis, for up to at least 3 mating bouts. All that is needed is a days rest in between.  That’s some serious sexual stamina.

But, why peel off the penis?

The sea slugs are hermaphrodites, and participate in reciprocal matings where each inserts a penis into the partners’ vagina.

Transparent penises of the hermaphroditic sea slug, S. quadrispinosum. From Lang et al. PLOS.doi:10.1371/journal.pone.0043234.g001

(This is a cool picture of a different species, showing the mutual mating tactic. p = penis. H= head of sea slug. s= stylet- a syringe like penis appendage that hypodermically stabs the other slug’s foot. More on this lovely mating duo to come).

It’s all quite civilized, really.  The thing is, though, this is likely not the only mating each slug has done recently.  Living in dense populations, they mate with each other ALOT. That means the female “side” of the slug may be storing sperm from several other suitors. So, as the male “side” retracts its penis after several minutes of mutual mating, tiny hooks along the penis head snag and ensnare sperm lining the vagina. This helps yank out the competition.

And, because a spiked penis is a bit difficult to retract (who wants to pull that sucker back inside their own body?), the slugs just ditch it, leaving their penis—and their competitor’s sperm—out to dry.  Having two more lengths of penis to unfurl means there is not too much to worry about in terms of lost mating opportunity.  Within 24hrs, they are ready to rock again.  Just goes to show how density of a population can select for some pretty crazy sexual strategies—where sperm competition isn’t so fierce, dudes tend to hang onto their dangles.

It must be tough for the guy to have to let go of his manly member. Even if he is also a she. Perhaps that’s why this strategy has only shown up in hermaphrodites: there’s enough female persuasion to get over any penis-attachement issues the male side may be holding on to…