The latest Carnival of Evolution is out (and would you believe I just almost spelled that “evilution”?)! It’s in two parts and full of great posts on many different aspects of evolution.

Go check it out!

Part #1, Part #2

evolution, biology, blog carnival

Here’s me grudgingly getting on the bandwagon and helping in the dissemination of the Tree of Life video with David Attenborough.

It’s very pretty. And all the facts are correct, so far as I’m aware. But this video still makes my skin crawl a bit. Why? Because it’s pretty much a perfect illustration of one of the problems I discussed in my post on tree thinking. Here’s evolution depicted as a linear process, with a clear line of progression from the simplest forms of life towards … well, humans, of course. What else?

They do mention insects invading land long before vertebrates did, which is nice. And there’s a short digression into dinosaur territory. But still - the video essentially supports a view of life where evolution inexorably works towards its goal, which is apparently primates with large brains. A tiny group of animals on an earth veritably crawling with other much more abundant forms of life. A self-centered, egotistical species, who cannot for a moment let go of the idea that we’re the pinnacle of creation, whether that creation was effected by a god or physical processes.

Also the video fails to point out that mammals came from the very same lineage Attenborough claims is ancestral to today’s tortoises, snakes, lizards, crocodiles and dinosaurs (including birds). It’s like mammals simply turn up by magic and start taking over the earth once the dinosaurs are gone.

And of course, there’s the glaring omission of the huge part of the tree of life that’s not animal. Plants and fungi are pretty much entirely ignored, bacteria are mentioned briefly and archaea not at all. This is ok, of course - the study of animals is obviously bound to be extra interesting to animals capable of appreciating said study - but I find it disingenious to call it a study of the tree of life when in fact we’re just looking at one of the several main branches.

But. It feels wrong to be critical of Attenborough. He has probably done more to popularise biology than anyone, and although he’s not a scientist he usually gets his facts straight (which, lately, feels more like a boon than it should) - so who am I to complain? Here’s a couple of things I really like about the video:

Firstly, Attenborough states that life began 3000 million years ago, rather than 3 billion. This is a very nice rhetorical trick to make people start realising just how vast a span of time we’re talking about. Graphically, the fact that the tips of the branches are all at the same level somewhat counteracts the idea that any living species is at the “top” of the tree. All living species are! Finally, the video does end with Attenborough pointing out that we mammals actually share the world with many other lineages.

So, Sir Attenborough, should you by any chance read this - I still love you. Just don’t do it again, ok? Now go to your room.

attenborough, tree of life, biology, evolution

Dear Britain: What the fuck?

Half of British adults do not believe in evolution, with at least 22% preferring the theories of creationism or intelligent design to explain how the world came about, according to a survey.

My first reaction upon reading this was: Kudos to the British public! Evolution does NOT explain how the world came about. Creationism actually does that better, since evolution doesn’t even attempt it. If the survey actually asked them if evolution explains “how the world came about”, no wonder the results were abysmal.

Now, the question is, was the survey really as stupid as the Guardian makes it out to be? This press release from Theos Think Tank seems to dispel that notion. It’s simply the case that the journalists and editors at the Guardian has gotten their heads stuck up their asses. Unfortunately, so do the people at Svenska Dagbladet, a Swedish newspaper that picked up the item and pretty much translated the article from the Guardian.

Why, journalists? Why must you make my job so difficult before I’ve even got one? I’m very nearly contemplating giving up my career plans as a biologist to become a science journalist intstead. At least I’d be halfway competent.

(And no, I’m not even touching the fact that the British public is in sore need of some good science education. With newspapers like the Guardian around to confuse people, I’d say the figures cited are pretty good.)

Hat tip to Terra Incognita and commenters.

ETA: Bob Churchill sets things right. Dear gods, the whole thing’s a mess when you think about it.

evolution, uk, science, journalism, science journalism

Since a few years back, Sveriges Ornitologiska Förening (Swedish ornithological association) has been involving the public in a great bird-counting exercise every January. Between dawn on a friday and dusk the monday after, we’re encouraged to keep track of what birds visit our bird feeders. More specifically we’re supposed to report the greatest number of each species observed at once. The resulting data is used to track fluctuations in bird populations all over Sweden.

It’s a fantastic way to involve the general public in scientific endeavours. The only thing I could wish for is that they’d push that side of things a little more - make people aware that that’s what they’re doing. Sure, the data is perhaps not as rigorous as would be required to publish in a scientific journal, but it’s definitely good enough for tracking changes and getting some idea of what’s going on.

Anyway, naturally me and my parents were keeping unusually close tabs on our own little feeding station over the weekend. This year our count was:

Great tit: >20. Probably at least 25. It’s very difficult to count when there’s that many!
Blue tit: 6. For a long time we spotted no more than two or three at the same time. Then we supplied an extra ball of fat (I have yet to find out what this might be called in English - it might be a scandinavian phenomenon. Looks like this.) and that brought them out of hiding.
Coal tit: 3. There might have been one or two more but we rarely see many of these at the same time.
Marsh tit: 2. Conspicuously absent most of the time. Marsh tit are normally regulars.
Yellowhammer: 2. And only for a brief time. We don’t supply oats so we’re probably not their favourite feeder.
Great spotted woodpecker: 1. Liked the peanuts but avoided the pig fat, oddly enough.
Nuthatch: 2.
Blackbird: 6. Mostly active at the crack of dawn when the other birds are barely awake. Likes apples.
Long-tailed tit: 6. Was so stoked to see a group of these absolutely adorable little tits on sunday. You know how some people go all gaga over cute puppies? That’s me with long-tailed tits. I start squeaking baby-talk for a few minutes.

These are pretty low figures and above all there’s several species missing. Where’s our friend the crested tit? Where are the jays? And what about the greenfinches and chaffinches? And my personal favourite the treecreeper? Part of the explanation is probably that weather has been pretty abysmal - above all it’s been too warm. When there’s no snow on the ground, the birds don’t particularly need the feeder. Many of them still show up, but nowhere near the great variety we see when it’s cold and snowy.

birds, bird feeding, ornithology

Darwin’s first tree

The following post is a crash course in how to interpret evolutionary trees written for the layman. I’ve avoided all the tricky nomenclature (like “phylogeny” and “cladogram”) for clarity. Enjoy!

As buds give rise by growth to fresh buds, and these, if vigorous, branch out and overtop on all sides many a feebler branch, so by generation I believe it has been with the great Tree of Life, which fills with its dead and broken branches the crust of the earth, and covers the surface with its ever branching and beautiful ramifications.
-Charles Darwin

When Darwin presented his theory on the origin of species by means of natural selection, he chose to illustrate the evolution of lineages by means of a tree. It’s a metaphor and a method that has stayed with us since then - for better or for worse. These days, we know that what evolution has produced is more of a sprawling shrub with mostly dead branches, rather than the majestic tree Darwin envisioned, and that the base of the shrub is probably more like a web than a trunk. (As most of you are no doubt aware by now, New Scientist recently had a story on this with a frightfully dumb headline on the cover.) These issues aside, depicting the relationship between species by the use of trees has turned out to be immensely useful.

Evolutionary trees are now ubiquitous; apart from being all over the scientific literature, they also turn up in museum exhibits, newspaper articles and wherever else the relationships of different species are discussed. Trees are a powerful and intuitive graphical representation of evolutionary relationships - but there are pitfalls. There is still a lot of confusion among people in general (and even biologists) when it comes to how these trees should be interpreted. We all have a tendency to read things and interpret images a certain way, and we often imagine an order of progression even when the data doesn’t support it. Many biologists don’t realise how important it is to choose a graphical representation of their data that isn’t just correct, but also doesn’t trick the viewer into believing conclusions that simply aren’t there; conclusions that have nothing to do with biology.

The ape branch

Case in point, take a look at the tree to the left. Humans are clearly at the top of this tree. It supports the idea that we are the pinnacle of evolution, the end result, perhaps even the reason for it all, don’t you think? No. In fact, the tree says that humans are entrenched among the apes, as much a primate as any of them. But since a lot of people haven’t learned “tree thinking”, that’s not what a lot of people see.

Because (at least in the west) we read from left to right, the tree depicted implies an order of progression from gibbons to humans. Some people would go so far as to interpret this tree as saying that gibbons evolved into orangutans, which evolved into gorillas, which evolved into chimps, which finally evolved into humans - the age-old “If humans came from monkeys, why are there still monkeys?” fallacy.

Gratuitous platypus

Even if you don’t fall into the progression trap, the tree still suggests at a glance that gibbons are more “primitive” than the rest. And this fallacy is something that’s not restricted to laymen. Some biologists would refer to the gibbon branch as “basal”, and it’s quite common to talk about “higher” and “lower” forms of life. This is all poor tree thinking. As long as all the species depicted in the tree are alive today, and as long as the assumption is made that life only begun once on earth, it’s important to remember that every single extant lineage has evolved for exactly the same amount of time. The “lowliest” of bacteria have been evolving for the same amount of time as us humans. We may say that some forms of life possess more “primitive characters” than others. For instance, monotremes are mammals that lay eggs, and since we believe that the ancestors of all mammals also laid eggs, we may call this a primitive trait - but that doesn’t mean that the monotremes are in some way less evolved than the rest of the mammals. They simply possess fewer derived traits.

So what can we say about this tree? What it tells us is that humans and chimps share a common ancestor that is more recent than the ancestor of humans, chimps and gorillas. The hypothetical ancestors are represented by the nodes of the tree. Conversely, it tells us that the lineage that would eventually become gibbons split from the rest earlier than the lineage leading to orangutans. It doesn’t say anything about what the hypothetical ancestors were - this tree in no way implies that the common ancestor of humans and chimps looked more like a human or a chimp. All we know is that it shared some traits with the lineage that led to the gorillas, which implies - to us, although the chimps might disagree - that that ancestor might have been more like the other apes than a human. Had the other apes been omitted from this tree and replaced by a fish, it would have been anyone’s guess as to whether chimps or humans possessed the most derived traits.

Finally I’d like to mention the concept of relatedness. When looking at a tree, how can you tell which species are more closely related to another? Firstly I would actually be wary of using the term “related” in this case at all. Rather than saying “this species is more related to that species than the third one”, I would say “these two species share a more recent common ancestor with each other than with this third one”. Because common ancestry is what this is all about. It is easy to look at a tree like the one above and get the idea that orangutans are more closely related to gibbons than to humans - they are adjacent to each other and only one node separates them. This is not correct. The common ancestor of orangutans and humans is more recent than the one of orangutans and gibbons, which means that orangutans and humans are more closely related.

Wrapping up, I present a very simple exercise for the reader! After reading this post you should be able to answer the following questions no problem, and as a little perk, the people who give me three correct answers will get to give me a topic or question of their choice to blog about (anything you like within reason - the more interested I am in the topic the better the post will be - if you ask me about the political situation in Nepal, or anywhere really, I’m afraid I’m stumped).

1. Are the trees below identical? (If not, how are they different?)
2. “In the first tree, species L is more closely related to species S than P.” True or false?
3. “In all trees, S, C and L share a common ancestor.” True or false?

biology, evolutionary trees, evolution, phylogenetics

Like John Whitfield at Blogging the Origin, I’m taking the opportunity to read Darwin’s On the Origin of Species now that it’s been 150 years since its publication, and 200 years since its author’s birth. I figure if I’m ever going to read it, now is the time. Unfortunately I’m not quite as fast as John, which means I’m not actually reading his blog, as I don’t want any spoilers.

Well, ok, I already know the book’s conclusion. But I want to experience each chapter without preconcieved notions and hence I’m putting off reading John’s comments until I’ve finished them myself … and I have yet to finish the first chapter. A few pages before going to sleep each night is the pace I’ve set.

Since I’ve only just started I don’t have much to say, except that so far, I’ve quite liked it. Apart from his incessant abuse of commas (which I know is simply indicative of when it was written), Darwin’s a good author. I don’t see why people complain about the pigeons in the first chapter - I think it’s brilliant. Darwin knows he’s going to upset a lot of people with his ideas, and so he starts out with the deviously innocent topic of breeding pigeons. It’s fantastic.

What’s also fantastic is how he keeps touching on areas where I, as a mere biology student in the 21st century, could totally fill him in. Although he was, to my knowledge, unfamiliar with Mendel’s ideas on inheritance at the time, he still seems very close to the right idea, occasionally. Perhaps, if his brain hadn’t already been so chock full of all that knowledge, he’d have had the intellectual energy to do some experiments and put things together. As it is, he didn’t, and maybe that’s a good thing. Maybe, the world needed that time of uncertainty to adjust, before the modern synthesis happened.

Anyway, I must say it’s a lot easier to read than I thought it would be. I’ve read most of Voyage of the Beagle already, and thought the Origin would be heavier, but it isn’t.

Expect more posts on the On the Origin!

darwin, origin of species, evolution

So, been a bit of a hectic week. The course in Molecular Ecology I mentioned finished on friday, meaning I spent the days prior to that frantically trying to finish the paper and presentation of the final project. It was on butterflies.

…

Oh alright. Here’s part of the introduction (the only interesting part of the paper, in my opinion):

The mating behaviour and associated pheromones of pierid butterflies, among them the green-veined white butterfly P. napi, have been studied extensively by Andersson et al. (2000, 2003 & 2004). These butterflies are polygamous, with males seeking out and courting females, which may then allow or refuse copulation.

During copulation, the male P. napi transfers a spermatphore to the female’s bursa copulatrix. This packet contains not only sperm, but also nutrients and pheromones, and is quite large – the mass can extend to 23 % of the female’s body weight. Recently mated females hence cannot receive another packet until they have absorbed the old one (Forsberg & Wiklund, 1989). Also, both mating and oviposition must take place during fair weather, which restricts the time a female can spend on both activities. Thus, females should be allocating more time for oviposition than mating when they are recently mated. This is facilitated by an anti-aphrodisiac transferred to the female during mating. The anti-aphrodisiac, methyl salicylate, is synthesised only by males.

When approached by a male, the female adopts a so called “mate-refusal posture”: She spreads her wings and lifts her abdomen. This posture is well suited for spreading pheromones from her abdomen, while at the same time preventing the male from copulating with her. Females initially adopt this posture regardless of whether they are receptive to mating or not. Receptive females will however, after having been courted by the male, lower their abdomen so that copulation may ensue. Males will approach any female, but quickly abandons recently mated and thus unreceptive ones – it appears that males are incapable of forcing females to accept their spermatophores, and hence they have no incentive to court an unreceptive female.

Females who have received methyl salicylate are thus less likely to suffer extended harassment from unwanted suitors, and can spend more time laying eggs. This also benefits the male, as it maximises the amount of his sperm that is used before an eventual remating. This is an interesting example of how sexual selection may sometimes lead to co-operation between sexes, rather than sexual conflict.

Stand back - I’m going to try science.

Thrilling, isn’t it? Our study, conducted over the course of about ten days, was quite simple. Our task was to find out whether males can utilise three different compounds to synthesise the anti-aphrodisiac. In the picture I’m posing with a gas chromatographer coupled to a mass spectrometer, used to identify volatiles emitted by male butterflies.

Oh you wanted to know the results? They could use two of the compounds we tested but not the third. That’s pretty much it.

Yeah, this is not my subject. The other two groups had more fun projects - paternity analysis in arctic foxes and phylogeography of … some other butterflies. They got to work with DNA! I was intensely jealous, but at least now it’s over. (And I got a B on the course. This corresponds to 85-95% correct marks on an exam so I’m quite happy.) Also, the next course I’m taking, which begun yesterday, is Molecular Systematics. So it’s pretty much guaranteed to be fun.

biology, science, pheromones, butterflies

There must be something wrong with the link between my science gland and the pleasure centre of my brain. I mean, normally a story like this would have me a-jitter with excitement. But for some reason, it fails to enthuse me.

So what’s up? Scientists have created (by means of an ingenious combination of intelligent design and natural selection) RNA molecules that can replicate. Except, well, personally I think “replicate” is rather a strong term. They copy themselves by assembling two smaller strings of RNA, rather than directly from nuclear acids (PZ Myers explains the process here). To me that doesn’t seem like that big a leap forward in the RNA World research. It’s one step in a long chain that might end up with something of supreme awesomeness - but we’re not there yet.

Cool stuff, but nothing I’d get overly excited about. (Or maybe I’m just stressed about the paper due on wednesday and having to turn my apartment upside down in anticipation of the new bed. Hard to tell with these things.)

evolution, rna

One of my most popular posts on this blog is Answers From an Atheist, where I answered a load of questions about atheism. In the same vein, I recently received an e-mail from a christian creationist who said he had encountered this blog, and asked if he could “show me some things”. Shrugging off the slight creepiness of that question I responded that I’ll be happy to spar with him so long as the “things” he wanted to show me didn’t come from Answers in Genesis. I also requested permission to post our exchange on my blog. He didn’t say no, so, here we are.

Before we start: If anyone wants to take me to task for being condescending and snarky, go right ahead. I am being a bit condescending and snarky. This guy engaged me via e-mail, rather than on my blog, which to me implies he has something really important to say. He wanted me to take the time to listen to his arguments and respond to him personally. I agreed, hoping he actually had something interesting to say, and then he sends me these confused rhetorical questions. Although I try to maintain an upbeat, friendly tone throughout my response, I can’t help if some snark poured through as well. I’m sure he means well and I hope he gets back to me (although I can imagine it’ll take him some time to get through my rambling), because I do enjoy a good verbal one-on-one.

Oh and if anyone finds fault in anything I say, please call me on it. My response was hastily written and not particularly well researched (although I’ve obviously come across the subject of the origin of sexes many times, I haven’t read anything in-depth about it recently). I don’t think there’s anything ass-backwards about it but one can never be too sure.

And, finally, if you’re a non-atheist or non-biologist with questions, please do ask! I’m no expert on either area but I love pretending to be one…

Are you willing to seek God’s existence? I certainly hope you do, because there IS evidence pointing to God.

This question is unanswerable except in the form of counter-questions:

1. Which “God” are you talking about? One of the many christian versions? Or any of the abrahamitic ideas of “God”? Or shall we branch out and include the gods of all living religions? Maybe, for good measure, the dead ones as well? I always thought grecian mythology was a hoot.
2. What evidence?
3. Do you realise it’s rather weird to ask someone to “seek” something before you present them with the evidence? Seeking God’s existence presupposes that he exists. Since I have no such presupposition, I look at the universe without religious eye-glasses, and see no evidence.
4. What do you mean by “willing”? I’m not unwilling to believe in god, I simply can’t believe in something that goes against the evidence. Are you “willing” to investigate the possibility that god actually doesn’t exist at all? Because believe me, the evidence is much better!

Do you believe the big bang formed the universe?

Since that’s the informed consensus of contemporary physicists, yes. It’s not my area of expertise so I’m happy to leave this question in more capable hands. Just like physicists are (for the most part) happy to leave the question about the evolution of life into the hands of biologists. Unfortunately, theologians often seem to do neither…

If so, then how come big bangs tend to cause detruction rather than creation any more?

I’m sorry, but what exactly do you think a “big bang” is? You seem to be confusing it with “explosion” or “loud noise”. As far as I understand it, the Big Bang was named such because it’s an easy visual - everything springing into existance at once, in a boiling hot soup of matter eventually coagulating into stars and planets. It makes our puny human minds think of explosions. But that doesn’t mean it actually was an explosion in the regular sense of the term. Besides, since the Big Bang entails something coming from nothing, and “something” is already in existence, the Big Bang can’t happen again, by definition - not in this universe, at any rate.

If the universe was formed by a big bang, things should still form by a big bang.

Non sequitur. If you were formed by your mother and father mating, you should still be forming by your mother and father mating. No? No. Something happening once does not necessarily mean it can and will happen again.

If I went to a junkyard, and got some old metal, and springs, then put them into a box, and shook it for a day, week, month, then a year, and all of a sudden BANG! A watch is formed by random chance, would you say that is logical?

“Logic” has nothing to do with it. This is about probability. And no, the probability of a watch being formed in that fashion is extremely low. What does this have to do with anything? I suspect that you think you’re saying something really smart about either evolution or the big bang, but I’m afraid you’re way off target - although I can’t say much about the big bang (as I said, I’m not a physicist), I can tell you that evolution is not purely driven by chance. Please look up “natural selection”.

One last question for now, What about reproduction? Let me explain: Almost all living organisms have to reproduce with one male, and one female. One connot carry life without the other. Which came first according to evolution? If the male evolved first, he could not have reproduced without the female, and vise versa How is it that both the male, and the female both randomly came into existance, ad they both evolved individual, and complex reproductive systems?

Ah, now, this question I can actually answer (to the degree that anyone can, I suppose)! See, reproduction is a very interesting part of life and its evolution, and one biologists spend a lot of time on (insert obligatory sex joke here). However, my answer will by necessity have to be rather brief and unsatisfactory, seeing as I don’t have time to 1. plow the literature for all the extra interesting tidbits or 2. write the series of books the subject deserves. Especially seeing as it’s already been done.

First of all, I’m glad you say “almost”, because … well, even with that caveat, you’re still completely wrong. Most living organisms are bacteria, and they do not have sexes - although they do carry out a fair bit of DNA exchange which may be seen as a sort of sexual behaviour. And among the sexually reproducing organisms, it’s still the case that when environmental conditions are stable, males are pretty much superfluous, so the idea that “one cannot carry life without the other” is also faulty. We’ll get to this in a bit.

So, how did sex start and why? First let me just say that obviously, we don’t KNOW. I’m going to present a hypothesis to you that is perfectly plausible, but I’m not saying it’s the gospel truth. The puzzle of how sex began is a big one, a whole field of research in itself. That you expect me to answer your question just like this says something about your disregard for the complexity and intricacy of biology as a research discipline.

Anyway. At some point, organisms evolved an ability and propensity for exchanging DNA with one another. What’s the benefit? According to one hypothesis, the benefit is evolution itself. Because the environment an organism and its decendants exist in is not static but ever-changing, carrying around the same old combination of genes for generation upon generation can be detrimental. Mutations that actually confer some sort of benefit are rare (most are completely neutral), and so organisms “invented” a way to introduce some variety.

This is the beginning of sex, and eventually it led to sex as we know it - where two gametes, each carrying half a genome, fuse to form a new individual. Since you’re specifically asking about how the sexes appeared, I’m not going to go more indepth about the theories of why organisms started having sex in the first place.

In the beginning of sexual reproduction, there were (probably) no males or females. Many species still don’t have sexes as we know them - there may be some small differences (we might call one individual +, another -), or in some cases, none at all. When there are no differences, everyone can mate with everyone in a free-for-all sex bonanza. However, reproduction is tricky and expensive - it costs time and resources. The more you invest in your offspring, the better your genes will fare in the next generation - but, the more you invest in each of your offspring, the fewer offspring you can afford to produce. So it’s not surprising that while some individuals evolved a propensity for creating large, well-supplied gametes, others evolved to “cheat”, producing small gametes that could fuse with the larger ones. Essentially, maleness and femaleness evolved side by side. If there’s a lot of female-type individuals around, producing a lot of big fat well-supplied gametes, it’s very advantageous to be a “cheater”, producing many small gametes that might fertilise the big ones.

Sex organs, the pretty kind

The point is, the evolution of maleness and femaleness - as defined by gamete size and motility - is really not weird at all. It’s no more odd than considering the co-evolution of parasites and hosts, or symbiotic relationships. Remember that it all happened very gradually and not overnight. And remember that the organisms that first evolved these traits were not the kind of animals that you’re thinking of, which have a whole arsenal of secondary sexual traits that are not intrinsically male or female but simply tacked on throughout the course of evolution. Thus your comment about “individual and complex reproductive systems” is also faulty, as the original males and females were simply individuals that produced slightly different gametes.

And, for the record, this is still very true for many, many organisms. In the ocean, the easiest way to reproduce is simply letting your gametes float away in the water and hopefully meet some other gametes on the way - this is how for instance corals do it. They do not have “individual and complex reproductive systems” - some of them produce big fat eggs, some of them produce small swimming sperm. That’s it. You, on the other hand, happen to be a mammal, and since mammals have the most weird and complex secondary reproductive traits of all, you think that’s what it means to be male or female. Sorry to let you down.

(I would go into why secondary reproductive traits - including breasts, uteruses and vaginas - might look the way they do, but this is already very long, so I’ll leave it for another time.)

And to come back to the superfluity of males, there are plenty of examples of organisms where males have more or less disappeared. Either the females reproduce by parthenogenesis (or as you religious folk like to refer to it, “virgin birth”), or the males exist as very rudimentary attachments living like parasites on the female. Imagine a scrotum attached to a woman providing her eggs with sperm. How does parthenogenesis work? If the environment is stable over time and you don’t need a partner to help raise your offspring, no sexual recombination of genes is required to keep your offspring fit, and this means that wasting time and energy on finding a mate is a bad idea. Females that evolve a way to produce offspring without male aid thus produce more offspring than those who do require males, and eventually the males disappear. This is really not at all weird - after all, females have everything they need to produce offspring - large, well-fed gametes. All they need to do is put ALL of their DNA in a gamete, instead of just half. Piece of cake. Males on the other hand couldn’t create offspring on their own even if their life depended on it, as the gametes they produce quickly starve and die.

I have attached an essay on reproduction I wrote a couple of years back, which explores the incredible variety of reproductive strategies among animals. I’d recommend you read through it before replying as I hope it’ll give you some apprecation of the complexity of the subject before you slag me off for being too cursory.

I obviously haven’t attached that essay to this blog post, but I do think I’m going to post it sometime in the fairly near future. Stay tuned.

religion, creationism, atheism, big bang, evolution, reproduction

Here we go again, back from another too-long, unannounced absence. And this time I failed to post a blog carnival, too!

(What happened? One thing: I was sick the days before it was to be posted and hence was unable to complete the carnival post as I only received like two submissions - TWO things: I was sick and only received like two submissions and then I couldn’t get hold of Irradiatus (who’s in charge of the carnival) - THREE things… you get where this is going. A number of circumstances conspired to stop me from posting the carnival, and then I was swept up in a flurry of real life activities precluding me from feeling inclined to blog much. Although I have no qualms about leaving my personal blog unattended, I feel horribly guilty about letting the Carnival of Evolution down. I will not offer to host a carnival again anytime soon, that’s for sure. I clearly can’t be trusted.)

So, what’s up? I’m on the last leg of a course called Molecular Ecology at the moment. It’s been good fun, studying a wide range of topics from population genetics to phylogeography to the use of pheromones in agriculture. It has definitely strengthened my resolve to focus on phylgenetics/systematics and historical biogeography in the future, as nothing makes my science gland tingle like those subjects. Unfortunately, I was handed a pretty dull topic for the last project on the course, so the last week is going to be a bit of a drag.

In other news, christmas has come and gone. If anyone’s curious about how a secular Swedish christmas is celebrated, I wrote about it last year. Also, on December 28 I passed the quarter-century milestone on my life’s journey (this being a very poetic way of saying I’m 25 and hence officially old - of course, if you ask my boyfriend, I’ve always been old, but on the morn of my birthday he upgraded me from “27″ to a “million billion years”). My birthday gift was a bed, which I’m very excited about, and which should arrive in a couple of weeks. Other news on the personal front include the fact that I finally caved in and took up WoW again. At the moment, however, I’m on a forced hiatus due to lack of money… And yes, I have used up my trials, thanks for asking.

On the humanism front, the Stockholm section of the Swedish Humanist Youth Organisation now has bi-weekly meetups at a café on Söder, which is good fun. One would think there’s a risk we run out of topics to talk about, but so far that hasn’t seemed to happen. After all, it’s not like we’re forbidden to discuss things outside of humanism. (Does sex count as on or off topic?) Also on the SHYO front, I co-authored an article in response to a letter to the editor in Kristianstadsbladet. It’s about morals, Darwin and nazis. I may translate it at some point. Tobias has also commented the letter on his brand new blog Yttranden (good luck with it, Tobias!).

That’s it for now. Now we all wait with baited breath to see how long I can keep it up this time…

humanism, biology, christmas