Sex? Sex? Oh, please. It's copulation.

In higher organisms, sex, gender, and copulation are all neatly tied up together such that to the less well informed (read science correspondent) they are one and the same. So when some science reporter says "Sex emerged in an ancient Scottish lake", and it turns out to be fossil fish copulating, it just sends the wrong message.  To be fair it's the headline that's wrong. The article clearly states this is about copulation. Sex is when parents of two different genotypes combine their genes in offspring, and it's much older than fish. There are algae, phytoplankton, that have sexual reproduction, and to some extent bacterial transformation might be considered a form of sexual reproduction, however, in this case, two parents only result in one offspring. TPP has a colleague in psychology who says he studies sex, but he really studies gender, where the two sexes are differentiated. That's not the case, at least not obviously, among many sexually reproducing organisms and we often use the term mating types designated by +/- signs. Then it gets really strange. Consider Ulva, sea lettuce, a green seaweed that looks like a limp leaf of lettuce. When you pick up a "frond" of Ulva, you don't know what you've got; it could be a plus, a minus, each with one set of chromosomes, or it could be a spore producer with two sets of chromosomes, all three physically identical, but parts of an alternation of generation life cycle. So let's be careful about throwing around the term "sex", besides the organism's name (Microbrachius dicki) makes for an even better joke regarding copulation.

Pepper sex? You must be kidding.

TPP just got this image by email, and if this is the way 2014 is going to go, it'll be a long year. 

Flip the bell peppers over to check their gender. The ones with four bumps are female and those with three bumps are male. The female peppers are full of seeds, but sweeter and better for eating raw and the males are better for cooking.

 

OK, there's the message that accompanied this image.  What a crock!  Fundamentally peppers, like most members of the nightshade family have 2 carpels (modified leaves) composing their pistil; those shown have 3 and 4 carpels because we've selected for bigger peppers so there are more units composing the fruits.  They can even have 5 sometimes.  Most of your smaller peppers have the standard two carpels.  The 4-lobed fruit will have one more placental ridge bearing seeds, but on average for the variety, in every other way they will be the same.  This is where a sample size of two, combined with someone who doesn't know any botany, led to a completely ridiculous assertion.  Fruits are part of the asexual phase of the plant life cycle so there are no sexes among fruit, and while the fruit are what develops from the floral "gynoecium", from the "ovary", there are no sexes here either, just popular, traditional, and very wrong names for flower parts.  Plant sex actually occurs at a different level, although people commonly refer to flower sex.  Pollen grains are dwarf males and way down inside the pistil, inside the "ovules" (actually megasporangia), the megaspore will develop into a very dwarf female.  So fruit sex is just pure bull.  No idea of the source, and it really doesn't matter.  A lot of crap floats around on the web, and at least this is harmless bogus information.  Surprised they could count that high. 

 

Bad day for biology teachers

Yesterday seems to have been a horrible, terrible, no good, very bad day for a couple of biology teachers. However, in only one of the two events was what they taught relevant. A biology teacher here in Lincolnland admits that he was teaching creationism in his high school biology class, but odds are the school board will tell him to never ever do it again and he'll continue teaching a horrid version of biology, rolling his eyes whenever mentioning that some biologists actually think something as bereft of evidence and as improbable as evolution could be true, teaching that will do more harm than the blatant creationism that any half intelligent high school student can see clear through. Please, please, please, let him not be a graduate of our university. Of course there'll be the usual "evolution is just as much of a religion" comments, but creationism isn't just wrong, it's useless; you can't use it to do science, and that's lost on all the critics of science. In Kentucky a female biology teacher was caught messing around with a high school student in a car. Scheesh! Get a motel room. No dobut about it, she'll be fired, and in all probability she was the better of the two at teaching biology. Maybe she graduated from Northwestern?

Naked truth about sex, gardening, religion, and politics in American government

In this day of binging and googling, buzzwords in a title can greatly affect the number of hits upon your blog or published article, but who would stoop to such a low and deceptive device? Since botany is in one of the little traveled back waters of biology, and most of biology isn’t trendy enough to matter to the media, it would appear that the Phactor has never used one of these academically trendy buzz words in any title of any published article. He did publish ‘the best pun ever used as a title” (according to one reviewer) and it attracted a great deal of attention to a small, but quite clever, bit of research, so buzzwords appears to work, but by now you should have realized that you are a data point in an experiment. We’ll report back to see if the traffic on this article is affected by the gratuitous use of buzzwords in the title. Which buzz word do you think will have the greatest impact? Take the poll; you're part of the experiment anyways.

Tree clones: immortality and sex

The oldest organisms on Earth are clonal organisms. Plants seem to have the capacity for immortality because they have perpetually juvenile tissues (meristems) capable of continued growth, and further, certain plant cells can dedifferentiate, return to a juvenile state, for wound repair and growth. This capacity is widely used in the vegetative reproduction of economically important plants. But can a clone live forever? Probably not, but they can be very old. The Pando clone of quaking aspen in Utah is estimated to be at least 80,000 years old, and some estimates place its age as 10 times older, which would make this clone as old as our whole species! Not only is Pando impressively old, it’s big covering over 40 hectares and at over 6000 tons is the largest organism alive. Now of course one problem with being an immobile species is that the longer you live the more likely you’ll encounter some environmental disaster, a fire, a flood, a volcanic eruption, a storm, a chain saw. But clones have a sex problem. Since they are all one genetic individual although looking like a whole forest, they cannot produce seed except by exchanging pollen with another individual, and when one individual occupies the whole area that becomes less likely. Even worse recent research suggests that as the clone gets older, it loses sexual vitality because of an accumulation of mutations. These show up in pollen because pollen only has one copy of each gene so if a harmful mutation occurs it may affect the viability of the pollen, a harm that does not affect the tree because in its tissues chromosomes and genes occur in pairs. By the relatively young age of 20,000 fertility can be diminished by more than 3/4s. So the clone may live a long time, but as it ages, its ability to sire offspring and start a new individual drops, but who knows Pando may already have lots of offspring.

Massive simultaneous algal orgy

Sex is always a good topic although mostly people have the wrong idea. From the biological perspective sex is production of genetically diverse offspring via mating. Most organisms, which are mostly unicellular, reproduce asexually, so all their offspring are genetically identical, a clone. And this works so well and so efficiently that sex among some organisms is a rare event in nature, so when biologists witness one, they get excited, intellectually.
In this instance the organisms are two species of diatoms, unicellular algae that are phytoplankton, the grass of the oceans. Diatoms are pretty nifty because their cell wall is made of glass, in two halves that overlap each other rather like a petri dish. This poses a bit a biological problem because a cell cannot bend or stretch a glass cell wall so when the cell reaches a certain maximum size for its cell wall the cell divides, which is how it reproduces asexually. The two daughter cells each inherit one-half of their progenator's cell wall, and synthesizes a new inner half. This means one of the two can grow as large as the original cell, but the other having inherited the slightly smaller inner half, so it's maximum size is constrained and it becomes a bit smaller.
Now think forward. When each of these two cells divide, the larger of the two produces two daughter cells just like the two described. But when the other daughter cell divides the biggest one daughter can get is the slightly reduced size of the maternal cell, but the other receiving the inner half of the cell wall is smaller yet. Now let's do this thousands of times. Some diatoms will still be as big as the original cell, but lots of lineages were getting smaller and smaller. At some point the smaller cell size triggers sexual reproduction where the smaller cells divide into gametes, sex cells, which escape their glass prison, fuse with a suitable mate, forming a new cell that enlarges to an optimal maximum size for a diatom, synthesizes a new cell wall and starts the whole process all over again.
The environment plays a role in such events because you don't want to be the only organism at an orgy to release your gametes into the big broad ocean. So what happened here was some environmental event triggered sexual reproduction in two species of diatom simultaneously, and someone was there to watch (record some data).
Whew! Sort of gets you all sweaty just thinking about it.