ADVERTISEMENT
  About the SA Blog Network

Posts Tagged "reproduction"

Culturing Science

Why Sociable Weavers Nest Together

assimilation-1-small

Dillon Marsh’s photographs of sociable weaver nests, taken in the Kalahari Desert of Southern Africa, beautifully illustrate traditional nature–the realm of wild animals–overlapping with human civilization. The apparent bales of hay draped over the tops and sides of telephone poles are home to hundreds of songbirds, which construct and maintain their monstrous nests communally. While [...]

Keep reading »
Extinction Countdown

The Incredible Mr./Mrs. Limpet: The Endangered, Sex-Changing Sea Snail

limpet

Understanding how an endangered species breeds and reproduces can be one of the first steps toward learning how to save it from extinction. A team of scientists working to conserve the nearly extinct sea snail known as the ribbed Mediterranean limpet (Patella ferruginea) have discovered an important clue about its reproductive strategy: it can change [...]

Keep reading »
Extinction Countdown

Sperm Bank and Reproductive Research Could Help Save Tasmanian Devils from Extinction

Tasmanian devil

A diseased and emaciated Tasmanian devil (Sarcophilus harrisii) was found last week on a golf course in the town of Zeehan on Tasmania’s west coast. Like many of its kind, the animal suffered from the deadly, transmittable cancer known as Devil Facial Tumor Disease (DFTD), which has wiped out at least 70 percent and possibly [...]

Keep reading »
Extinction Countdown

Last Wild Camels in China Could be Saved with Embryonic Transfer Technique Perfected in U.A.E.

The critically endangered wild Bactrian camel (Camelus ferus) is so rare and lives in such remote areas that it was only recognized (after a few years of scientific debate) as its own species in 2008, decades after China started using one of its few habitats, the the Lop Nur Desert, to test nuclear bombs. Amazingly, [...]

Keep reading »
Guest Blog

Superfetation: Pregnant while already pregnant

Some weeks back, I came across a case report published in 1999 in the journal Ultrasound in Obstetrics and Gynecology [1]. It presented a twin pregnancy wherein one of the fetuses seemed to be at a younger developmental stage in its mother’s womb compared to its sibling. It wasn’t the first time that I had [...]

Keep reading »
Guest Blog

I don’t have a 28-day menstrual cycle, and neither should you

Most of us are familiar with a 28-day menstrual cycle, which, divided in half, comprises the follicular phase – that’s when the dominant follicle, or egg, is growing and preparing for ovulation – and the luteal phase – when the endometrium, or lining of the uterus, is preparing for possible conception and implantation. If implantation [...]

Keep reading »
Guest Blog

We all need (a little bit of) sex

"The males of the four salamander species whose genomes can be found in unisexual species. From left to right: A. jeffersonianum, A. tigrinum, A. laterale and A. texanum."

Sex costs amazing amounts of time and energy. Just take birds of paradise touting their tails, stags jousting with their antlers or singles spending their weekends in loud and sweaty bars. Is sex really worth all the effort that we, sexual species, collectively put into it? Despite many teenage frustrations and MTV, most biologists think [...]

Keep reading »
Observations

Baby Mice Born from Eggs Made from Stem Cells

mouse egg stem cell babies

Stem cells have been coaxed into creating everything from liver cells to beating heart tissue. Recently, these versatile cells were even used to make fertile mouse sperm, suggesting that stem cell technology might eventually be able to play a role in the treatment of human infertility. Now two types of stem cells have been turned [...]

Keep reading »
Observations

Moss Sperm Smells Sweet Enough for Sex

moss uses bugs to spread sperm

Moss, that cushy, moisture-loving ground cover, is more promiscuous than we thought. These plants might not have the sexy flowers of a peony, but according to new research, they do manage to attract small pollinators with a subtle sweet smell. Previously, scientists had presumed that these primitive plants needed a layer of water for their [...]

Keep reading »
Observations

For Unendowed Fish, a Fake Dinner Leads to Sex

fish lure sex food

The promise of a nice dinner might not always win over a woman, but for some male fish, a tasty-looking lure seems to get the girl pretty reliably. The trick is to make sure the offering resembles the local cuisine and then they can reel in the ladies hook, line and sinker. Swordtail charachin (Corynopoma [...]

Keep reading »
Observations

Poor Diets Lower Sperm Counts

sperm count

Fellas, want a better chance of passing along your genes? Try laying off the fried food. A more healthful diet will not only help you get fitter, but, new research indicates, it might also increase the odds that your sperm are in better shape, too. A whole host of factors might impair male fertility—including alcohol [...]

Keep reading »
Observations

Dogma Overturned: Women Can Produce New Eggs [Video]

A study led by Jonathan Tilly of the Massachusetts General Hospital overturns the decades-long idea that women are born with all the eggs they will ever have. It reports that women of reproductive age carry ovarian stem cells, meaning that they can produce new eggs. Tilly’s team, which made a similar finding in mice in [...]

Keep reading »
Observations

Jurassic Mammal Moves Back Marsupial Divergence

Juramaia sinensis

A newly described pointy-nosed, rat-like animal did not just crawl out of some unsuspecting city’s sewers. Rather, this now-extinct species spent its time scampering among prehistoric trees some 160 million years ago during China’s Jurassic period. Its modern appearance might seem unremarkable, but its advanced anatomical features—both internal and external—are exactly what have drawn the [...]

Keep reading »
Observations

The warm, fuzzy side of climate change: Heftier marmots

marmot that has gotten bigger with climate change, longer summers

While polar bears flounder in the face of shrinking ice floes, another furry creature has gotten a boost from climate change. In the past three decades yellow-bellied marmots (Marmota flaviventris) have been fruitful—and multiplied—thanks to longer summers, according to a new study. In the Rocky Mountains, these marmots usually hibernate for seven to eight months [...]

Keep reading »
Observations

Which sperm will win the race to the egg: the green one or the red one?

Once they’re inside the female reproductive organs, sperm pull out all the stops to outrace their rivals to the egg—especially if the opponent comes from another male. The process that determines which sperm wins, called "postcopulatory sexual selection," has been difficult to tease out, until now. By genetically engineering fruit flies that express green or [...]

Keep reading »
Octopus Chronicles

How To Grow a Patagonian Red Octopus

octopus eggs

Octopuses are tricky animals to keep in captivity. They’re smart, strong and slinky. But surely their eggs much be easier—being naturally contained and all. Not always, it turns out. Researchers in Chile have been on a quest to grow a local octopus species in captivity after it was overfished in the wild. The results of [...]

Keep reading »
Octopus Chronicles

16 Arms + 6 Hearts = Love? Watch an Octopus Blind Date Live

octopus date love

  This Valentine’s Day, two octopuses are getting set up on a blind date. And you can watch what happens. Ace, a male giant Pacific octopus (Enteroctopus dofleini) between 40 and 50 pounds and two-and-a-half to three-years old, and YoYo, a female of a similar size and age, will be introduced for the first time [...]

Keep reading »
Octopus Chronicles

National Zoo’s Octopus Dies in the Company of Her Favorite Toy—a Kong

pandora octopus

Pandora, the Smithsonian’s National Zoo’s giant Pacific octopus (Enteroctopus dofleini) died at her Washington, D.C. home (tank) Wednesday at the advanced age of five. She stretched more than eight feet across and was the zoo’s longest-lived octopus. Earlier this week, Biologist and keeper of the invertebrate exhibit, Tamie DeWitt, wrote in an email that, “for [...]

Keep reading »
Octopus Chronicles

Odd Male Octopus Flaunts 2 Unexpected Arm Phalluses

octopus arm phallus hectocotyli

Is that a case of bilateral hectocotylization, or are you just extra happy to see me? Or so might a female octopus say if she met the young subject of a new report about a certain biological oddity—or oddities. A rare juvenile octopus was captured off the coast of Alaska flaunting not one but two [...]

Keep reading »
Octopus Chronicles

Octopuses Make Food for Weird Critters

octopus feed

Along with us humans, a range of hungry hunters prey on the scrumptious octopus. The boneless octopus must avoid becoming lunch for sharks, eels, fish and even killer whales. But not all of the organisms that feed on octopuses are such charismatic megafauna. Octopuses, both dead and alive, are part of the delicate, detailed food [...]

Keep reading »
Octopus Chronicles

Happy Octopus Day! The 8 Best Octopus Discoveries

October 8 might be International Octopus Day, but October 31, 2013 is Octopus! day. My book Octopus! The Most Mysterious Creature In the Sea is publishing today. For the book I was able to travel the world, searching high and low for the most astounding octopus experiences. It was a nine-month whirlwind, spending vacation days [...]

Keep reading »
Octopus Chronicles

Hey, How Old Is That Octopus?

octopus age

Trees have rings, horses have teeth and even rocks have radiocarbon decay. But how can you tell an octopus’s age? This isn’t a frivolous question. In fact, the future health of octopus populations depend on it. To meaningfully study any animal population, scientists need to be able not only to count the individual numbers (already [...]

Keep reading »
Octopus Chronicles

First Octopus Farms Get Growing

octopus farms

Fish farms now produce million tons of fish each year around the globe. But octopuses have largely escaped this kind of confined aquaculturing, despite a growing global demand and overfishing. Why? That’s the million-ton question. Based on their brief life cycles, prolific reproduction and efficient metabolisms, octopuses should be ideal candidates for aquaculture. They have short [...]

Keep reading »
Octopus Chronicles

Octopus Babies Hatch by the Thousands, Captured on Video

octopus baby hatch

Octopuses live short, lonely lives. Even the big ones only see a few years. And that usually means only one shot at creating the next generation—and they don’t have time for parenting. So they up the odds of passing along their genetic legacy by making lots of babies, as in thousands and thousands of babies. [...]

Keep reading »
Octopus Chronicles

Unusual Offshore Octopods: Deep-Sea Octopus Hatches Fully Formed, Walks Away [Video]

octopus walk egg hatchling

Most octopuses take the million-to-one-odds strategy when it comes to reproduction. They lay thousands—if not tens or hundreds of thousands—of tiny eggs. Out of these hatch bitty proto-octopuses, which drift around with other plankton and paralarvae, at the mercy of currents and anything hungrier and larger than they are (which can even include their siblings). [...]

Keep reading »
Running Ponies

You’ll have to be hotter than that, virgin moths

Even moths can’t escape the tribulations of being a virgin. New research by scientists at the University of Utah has revealed that when a male virgin Helicoverpa zea moth picks up the scent of a female, it will stop at nothing to get to her as soon as possible, even if that means taking off [...]

Keep reading »

More from Scientific American

Scientific American MIND iPad

Give a Gift & Get a Gift - Free!

Give a 1 year subscription as low as $14.99

Subscribe Now >>

X

Email this Article

X