Beautiful, brutal ctenophores

February 28, 2013 • 11:54 am

by Matthew Cobb

Ctenophores (“teen-o-forz”), or ‘comb jellies’ are some of the most beautiful organisms in the ocean. They are generally transparent, and biradially symmetrical, so they have infinite planes of rotational symmetry. As if that wasn’t enough, they have beautiful ‘combs’ along their edges, which shimmer in the light as they move the animal around, using simple muscle cells. This gives you an idea of how beautiful they are:

comb jelly

Their prey, however, may not find them so beautiful, and their eating habits are anything but elegant. Here’s a video of ctenophores (Bereo ovata, apparently) just swallowing other ctenophores (Mnemiopsis macrydi). The mouth on the first snarf looks so human-like I wondered if it wasn’t CGI, but it isn’t. It’s just life in all its gory glory:

Ctenophores are not jellyfish. They don’t sting and they are never colonial organisms. Strikingly, they have a peripheral nerve net and can respond to gravity and perhaps light. This video filmed in the Arctic sea off Svalbard in Norway shows that they can separate the wheat from the chaff when it comes to eating their prey:

True facts about the ctenophores:

• 150-200 species

• Found at a range of depths

• Grow from 2mm – 2m in size

• They have a mouth at one end, and an apical sense organ at the other

• They have a blind gut (which you can see on these videos)

• They eat zooplankton, small fish, and even ctenophres

• They are selfing hermaphrodites (ie they do it with themselves)

• The fertilized eggs are released into the water and develop into mini-adults in 24 hours

In 2008, a paper in Nature suggested that the ctenophores might be on a different branch of life from the rest of the animal kingdom. However, they authors themselves said:

The placement of ctenophores (comb jellies) as the sister group to all other sampled metazoans is strongly supported in all our analyses. This result, which has not been postulated before, should be viewed as provisional until more data are considered from placozoans and additional sponges. If corroborated by further analyses, it would have major implications for early animal evolution, indicating either that sponges have been greatly simplified or that the complex morphology of ctenophores has arisen independently from that of other metazoans.

Nature 452, 745-749(10 April 2008)

An initial study of the first ctenophore genome to be sequenced Mnemiopsis leidyi (a close relative of the victim in the video above) suggested that sponges and ctenophores first branched off from the rest of the animal kingdom (Ryan et al, 2010):

Tree

Joseph F Ryan, Kevin Pang, James C Mullikin, Mark Q Martindale, and Andreas D Baxevanis (2010) The homeodomain complement of the ctenophore Mnemiopsis leidyi suggests that Ctenophora and Porifera diverged prior to the ParaHoxozoa EvoDevo. 2010; 1: 9.

 

h/t  @hannahjwaters on Twitter

Andrew Sullivan suspects that Pope Benedict is gay

February 28, 2013 • 11:36 am

Andrew Sullivan, gay activist, staunch Catholic, and blogger, has a pretty incendiary post up at The Dish.  I reproduce part of it without comment, except to say that someone who is gay is more likely to be an accurate detector of gay behavior:

But this is what really made me sit up straight, so to speak:

Benedict’s trusted secretary, Monsignor Georg Gänswein, will be serving both pontiffs — living with Benedict at the monastery inside the Vatican and keeping his day job as prefect of the new pope’s household. Asked about the potential conflicts, Lombardi was defensive, saying the decisions had been clearly reasoned and were likely chosen for the sake of simplicity. “I believe it was well thought out,” he said.

So Benedict’s handsome male companion will continue to live with him, while working for the other Pope during the day. Are we supposed to think that’s, well, a normal arrangement? I wrote a while back about Gänswein’s intense relationship with Ratzinger, while noting Colm Toibin’s review of Angelo Quattrochi’s exploration of Benedict, “Is The Pope Gay?”. Here’s Toibin getting to some interesting stuff:

Gänswein is remarkably handsome, a cross between George Clooney and Hugh Grant, but, in a way, more beautiful than either. In a radio interview Gänswein described a day in his life and the life of Ratzinger, now that he is pope:

The pope’s day begins with the seven o’clock Mass, then he says prayers with his breviary, followed by a period of silent contemplation before our Lord. Then we have breakfast together, and so I begin the day’s work by going through the correspondence. Then I exchange ideas with the Holy Father, then I accompany him to the ‘Second Loggia’ for the private midday audiences. Then we have lunch together; after the meal we go for a little walk before taking a nap. In the afternoon I again take care of the correspondence. I take the most important stuff which needs his signature to the Holy Father.

When asked if he felt nervous in the presence of the Holy Father, Gänswein replied that he sometimes did and added: ‘But it is also true that the fact of meeting each other and being together on a daily basis creates a sense of “familiarity”, which makes you feel less nervous. But obviously I know who the Holy Father is and so I know how to behave appropriately. There are always some situations, however, when the heart beats a little stronger than usual.’

This man – clearly in some kind of love with Ratzinger (and vice-versa) will now be working for the new Pope as secretary in the day and spending the nights with the Pope Emeritus. This is not the Vatican. It’s Melrose Place.

I have no idea whether Sullivan’s suspicions are correct, and, of course, there’s nothing wrong with being gay. But there is something wrong— something deeply hypocritical—about being gay and, at the same time, helping lead an institution that condemns gays and sees gay behavior as sinful acts of “grave depravity” and as “intrinsically disordered.” We already know that many members of the Catholic hierarchy who condemn gays nevertheless engage in that behavior (or in child rape) themselves.

At any rate, Benedict will be Pope Emeritus as of this evening.

_______

p.s.  In today’s New York Times, theologian and author Hans Küng outlines what kind of Pope the Catholic Church needs. Hint: one who does not espouse medieval theology like Benedict did.

Squirrel report

February 28, 2013 • 8:49 am

There are actually two squirrels involved in building the nest on my office windowsill, so I have hopes for a brood of babies later this spring. In the meantime, twigs continue to accumulate and, as per Ben Goren’s suggestion, I have cut up strips of soft, clean socks for them to use as nesting material.

At the moment I have only peanut butter to feed them, and I understand the problems with this food, but I’m going to buy some seeds and nuts in the next few days.

Here’s their current situation (a dollop of Skippy on the right).

P1000282

Why assault weapons?

February 28, 2013 • 5:37 am

California Senator Dianne Feinstein has introduced into the U.S. Congress proposed legislation that would ban military-style assault weapons. The weapons proposed for banning are semiautomatics, those having large magazines and that fire one round each time you pull the trigger, automatically ejecting the spent cartridge and loading the next into the chamber. You don’t have to reload until many bullets have been fired. Here’s one of them, the An Intratec TEC-DC9 with a 32-round magazine. It’s legal:

Kg99

What possible civilian use can such a weapon have? Certainly not for hunting, and if you want to protect yourself or an intruder, there are handguns and rifles with smaller stores of ammo or bolt action reloading.

Sadly, the Republicans in Congress (under pressure from the National Rifle association) oppose this, and it is unlikely to pass. Other pending legislation requiring background checks of gun purchasers, including those at gun shows, has also been stalled because of Republican opposition.  These two initiatives are part of President Obama’s push to tighten up gun laws and make it harder to conduct mass killings like those at Newtown. That too, will amost certainly fail.  As the Los Angeles Times reports:

Although negotiations continued, no progress on background checks appeared evident in the Senate, where a bipartisan group struggled over how to broaden them. The major sticking point: whether private citizens who sell guns directly to others should be required, like licensed dealers, to keep records of the sale.

Gun rights backers warn those records could be used to create a national registry of gun owners, which they oppose.

Sen. Tom Coburn (R-Okla.), one of the key negotiators, said this week that any provision that required gun owners to keep records would “kill this bill.” Instead, he said, legislation should give sellers “the right and the responsibility to do the right thing” and run a background check.

Gun control advocates say that without a paper trail, it’s impossible to know whether background checks have been performed, opening a loophole for criminals to buy guns.

And without a paper trail it’s hard to trace back weapons used in assaults.

Here’s a summary of Feinstein’s Assault Weapons ban of 2013 from her website:

The legislation bans the sale, transfer, manufacturing and importation of:

  • All semiautomatic rifles that can accept a detachable magazine and have at least one military feature: pistol grip; forward grip; folding, telescoping, or detachable stock; grenade launcher or rocket launcher; barrel shroud; or threaded barrel.
  • All semiautomatic pistols that can accept a detachable magazine and have at least one military feature: threaded barrel; second pistol grip; barrel shroud; capacity to accept a detachable magazine at some location outside of the pistol grip; or semiautomatic version of an automatic firearm.
  • All semiautomatic rifles and handguns that have a fixed magazine with the capacity to accept more than 10 rounds.
  • All semiautomatic shotguns that have a folding, telescoping, or detachable stock; pistol grip; fixed magazine with the capacity to accept more than 5 rounds; ability to accept a detachable magazine; forward grip; grenade launcher or rocket launcher; or shotgun with a revolving cylinder.
  • All ammunition feeding devices (magazines, strips, and drums) capable of accepting more than 10 rounds.
  • 157 specifically-named firearms (listed at the end of this page).

The legislation excludes the following weapons from the bill:

  • Any weapon that is lawfully possessed at the date of the bill’s enactment;
  • Any firearm manually operated by a bolt, pump, lever or slide action;
  • Assault weapons used by military, law enforcement, and retired law enforcement; and
  • Antique weapons.

The legislation protects hunting and sporting firearms:

The bill excludes 2,258 legitimate hunting and sporting rifles and shotguns by specific make and model.

My question is this:  why is there any reason for civilians to own such weapons? They’re not for hunting, and, as I noted, you can protect yourself without huge-magazine semiautomatic weapons. They have only one use: to kill large numbers of people.

How is the possession of such weapons justified? I know that the “background-check” legislation is opposed because of the ridiculous idea that it would put America on a slippery slope, at the bottom of which is complete prohibition of all guns for civilians (something that I favor, by the way).  But that argument is ridiculous: you can ban alcohol for those over 18 without that leading to a total ban on alcohol.

But are assault weapons defended with the same “slipperly slope” argument? (I doubt that, because we already have a ban on fully automatic weapons, and that hasn’t led to complete prohibition of guns.) Or is there some argument I don’t know that even a stupid Republican can offer in defense of these weapons?

The Republican Party is not only the party of the rich, but the party of mass killings. It favors a dysfunctional America, and I wouldn’t be upset if every Republican in Congress lost their seat.

Ice age art

February 28, 2013 • 5:08 am

Perusing the latest stuff from the journal Nature, I found this lovely video of a new exhibit at the British Museum featuring some of the oldest artwork known—including pieces made 40,000 years ago. That’s not too long after the “out of Africa” event that spread modern Homo sapiens through the world! Take a look at the “lion man” in the first clip

Here are the movie notes. If you’re in England, go see this, though it costs ten pounds to enter (note, though, that the rest of the British Museum is free).

A new exhibition at the British Museum in London features sculptures made up to 40,000 years ago. Dr. Alice Roberts meets curator Jill Cook to discuss three artefacts in the collection; the Lion Man, a group of female figurines from Siberia, and the oldest known musical instrument. Despite being made thousands of years ago, the objects show that the minds of their creators – our ancestors – were incredibly similar to our own.

When the flute shown in the video was first discovered the finding was published in NatureNew flutes document the earliest musical tradition in southwestern Germany.
‘Ice Age art: arrival of the modern mind’ runs at the British Museum until 26 May 2013. http://www.britishmuseum.org/whats_on…

Here are some pieces from the BM’s website on the exhibit; they (and the video above) show that there were already accomplished artists tens of thousands of years ago.

The oldest known portrait of a woman sculpted from mammoth ivory found at Dolní Vestonice, Moravia, Czech Republic. approximately 26,000 years old
The oldest known portrait of a woman; sculpted from mammoth ivory found at Dolní Vestonice, Moravia, Czech Republic. approximately 26,000 years old
Spear thrower made from reindeer antler, sculpted as a mammoth. Found in the rock shelter of Montastruc, France. Approximately 13,000–14,000 years old
Spear thrower made from reindeer antler, sculpted as a mammoth. Found in the rock shelter of Montastruc, France. Approximately 13,000–14,000 years old
Tip of a mammoth tusk carved as two reindeer depicted one behind the other. Approximately 13,000 years old, from Montastruc, France
Tip of a mammoth tusk carved as two reindeer depicted one behind the other. Approximately 13,000 years old, from Montastruc, France

OMG: a squirrel builds its nest on my windowsill

February 27, 2013 • 1:35 pm

For the past few days I’ve been hearing scuttling noises outside my window. Since I keep the blinds closed by my desk, as the sunlight makes it hard to see my computer, I thought it was just snow or ice falling off the roof. Yesterday, however, I opened the blinds because the noise was insistent.  And, lo and behold, I found an eastern gray squirrel (Sciurus carolinensis) building a nest on my windowsill.  It (sex is indeterminate yet, and both sexes build nests) is breaking off stems of Virginia creeper to make the framework, and rearranging the twigs in what seems to be a haphazard manner (I’m sure there’s method in its madness, though).

squrl 2

I’m not sure why this crazed rodent was building a nest in the middle of a snowstorm, but maybe it’s preparing for baby season. I thought that squirrels also built nests to protect them from winter’s ravages, and it’s a bit late for that.

Sqrl 1

Right now there’s just a roughly circular pile of twigs, which the frenetic squirrel supplements and rearranges at random times.

I will of course keep readers updated on what happens next.