Apr 25, 2008

Stars of Cyrene

We were out again this morning with Dr Lane to search for echinoderms, in particular, a Special Star that was seen two weeks ago.

We saw lots of wonderful stars and stuff (see links to more blog entries of the trip below).

But to me, these are the true stars of our shores!
The valiant volunteers who turned up in force to help in the search. And our hero is Vyna (here, the rose among the thorns) who in the last minutes of the dying low tide, found The Star!

Like paparazzi, everyone crowded around to have a shot at The Star.It was a real squeeze and poor Jerald couldn't get past the huddle.And what's the fuss about?

This!A beautiful jewelled star (Pentaceraster sp.) that resembles our more commonly seen Knobbly sea star (Protoreaster nodosus), represented by the small star in the photo. The small Knobbly was unceremoniously tossed aside as everyone focused on The Star.

Why is The Star so special?

Because Dr Lane says it's the first record of it in Singapore!

Unfortunately for The Star, fame means eternal glory in the collection of the Raffles Museum of Biodiversity Research. Other interesting observations today: Dr Lane pointed out that the huge bobbly snaptid sea cucumbers that we commonly see among the seagrasses...Have itty bitty crustaceans on them!!They were really tiny and hard to photograph. Amazing!

Dr Lane also explained that not all the big black long-spined sea urchins that we see are necessarily Diadema setosum just because they have an orange ring on the anal cone.He says this one could be Diadema savignyi as it has shorter spines and has blue lines on the body!Jerald also found a Knobbly eating something, and we show it to Dr Lane.Everyone finds all kinds of echinoderms.

Robin found the Cake sea star (Anthenea aspera), Sam found a baby Cushion star (Culcita sp.), Heok found a red feather star which later was found to have a black bristleworm-like thing on it. And probably lots more that I missed out on (check out the links to blog entries below).

And everyone saw lots of Knobbly sea stars of all colours, sizes and knob patterns.
There were also sand dollars, sea urchins, sea cucumbers, and lots and LOTS of Common sea stars (Archaster typicus).

This is quite amazing given the proximity of this submerged reef to the major industrial installations on Jurong Island and Pulau Bukom.Right smack next to major shipping lanes with humungous ships like this car-carrying ship passing close by.And just overlooking the container terminals and the city on the mainland.Well back to the stars.

They are unstoppable. All ready for action even before sunrise.Unfazed when told they need to work on a reef that only briefly shows above water during a short window of low tide.And requires an amphibious landing that involves leaping off a tiny boat.The volunteers have strange rituals, such as worship of the GPS Gods.But most importantly, our star volunteers need to eat.

Before the trip.And definitely after that...don't disturb them while they're feeding.Thanks to everyone who came today: Vyna, Andy, November, Marcus, Liana, Sijie, Kok Sheng, Jerald, Sam, Siti, Wei Ling, Robin and Dr Tan Heok Hui. And of course, Dr Lane for sharing so much with us.

More behind-the-scenes efforts: Intrepid volunteers during a TeamSeagrass visit first saw The Star. It was found by none other than our best hunter seeker: Chay Hoon. Marcus brought The Star's discovery to the attention of Dr Lane, and thus sparked off this trip. Kok Sheng also organised the hunt today to ensure there was as complete a search as possible despite the short low tide. And Sijie mobilised support in collection and follow up with the media. Look out for a story about this soon! And all this would not have been possible without the friendly and able support from the Dolphin crew.

Many hands and hearts come together to make discoveries possible.

Links to more blog entries about this trip

ACT for Cyrene!


Ron Yeo said...

Just want to highlight that in the book Dr Lane published, he claimed that D. setosum and D. savignyi are very alike, but D. savignyi lacks the orange-rimmed anal cone and the 5 white spots on the test.

He also mentioned that D. Setosum can be differentiated from other diadematids by the above mentioned characteristics. Seems like he's contradicting himself now.

Ria Tan said...

This is a good opportunity to highlight that not everything in books are written in stone.

Scientists continuously improve their knowledge.

Taxonomists continuously update and revise systematics as their studies discover new aspects.

Dr Lane studies echinoderms extensively and must have discovered something new to make this comment about the two Diadema. We did have a long discussion on the shore about the differences.

There are many stories of our own marine life which have been re-identified based on closer studies by scientists, e.g., the Giant mudskipper.

The nature of science is such that scientists will even 'contradict' themselves if it means working towards a more correct understanding.

So we should not be surprised by revisions, and should always be open to learn from experts who visit our shores.

Besides which, as you yourself have experienced, books can contain serious mistakes due to layout and page handling errors that despite efforts by the authors during the process are not corrected by final print time and errata are not issued thereafter.

Books are a helpful foundation, but should not be taken as the absolute last word throughout all time.

Ron Yeo said...

Actually, I hold a different view from you. The way I see it is, scientists may also be wrong, especially if the species is not the one which they have extensively studied on. As you know over the past few years I had the opportunity to meet several marine biologists, and I've noticed that their memory or knowledge is not always reliable. Thus these days I'll often try to verify what I heard with any resources I can lay my hands on.

Personally I have seen the various Diadema and Echinothrix species he mentioned, identified in aquariums overseas and also other published and online resources. The sea urchin identification guide I managed to lay my hands on so far also indicated that what he has mentioned to you and also Sijie are rather questionable.

I'm trying to grab hold of a taxonomist to check on his recent claims. Will keep you updated.

Monkey said...

What we understand as facts are often not truly 100% certain. Only because nobody else have been able to disprove it yet. That is the nature of science. We are constantly learning new things and disproving established "facts". That's how paradigm shifts occur.

Ria Tan said...

Scientists will be the first to say that they could be wrong.

Is Dr Lane an expert in Singapore echinoderms?

Dr Lane studied echinoderms in Singapore for 15 years including an 3-year study to document our echinoderms, with dive trips and dredging of our shores.

On the Raffles Museum of Biodiversity Research website, "For the last two decades, specimens obtained mainly from Singapore waters have been contributed by the Reef Ecology Study Team and David Lane"

He is currently at the University of Brunei Darussalam and a write up of him and his publications is found here

Ron Yeo said...

Unfortunately a lot of times it's the myopic leading the blind :)

The blind may believe everything the myopic says about how the world looks like, but does that mean it's the truth?

Science is about asking questions, even if the one providing the answer is deemed to be an expert, it's important to question his claims seek the views of other experts.

Especially when Dr Lane's focus now is on Asteroidea, and has been referring to taxonomy guides published in the 1970s, I think even him will agree that checking with other sea urchin experts will make more sense.

Anyway, am still trying to see if I can check with any other experts around to clear up any confusion. Don't want to get stuck the next time I see a sea urchin.

For one thing, have read that there are hybrids between the two Diadema species, but the orange anal rim and 5 white spots are still used as the definitive identifying characteristics for D. setosum so far.

Will update you guys if I manage to clarify anything.

sits said...

I think we shouldn't get our panties too much in a twist over taxonomy.

Ron Yeo said...

Finally managed to find a recent paper on sea urchin identification. Since getting published in a journal means it had been scrutinised by other experts in the field, I personally feel this paper is sufficient to show that the sea urchins everyone has seen on cyrene are indeed Diadema Setosum. Check out my blog for more details.

Ria Tan said...

In the journal article you quoted, definitive ID is based features of the test (skeleton of a dead urchin without spines) and genital plates (requires a microscope).

So firstly, it's difficult to be absolutely sure in the field, unless you intend to take out all the spines of an urchin, put it in alcohol and whip out a microscope to observe the genital plates.

Secondly, these distinguishing features identified in 2006 affect those outlined by Dr Lane in his book of 2003.

That is perhaps why Dr Lane 'contradicted' himself?

So, the point that Dr Lane was making is that urchins we think is D. setosum MAY be/COULD be D. savignyi.

Considering that Cyrene harbours rare echinoderms including a very large sea star that is a first record for Singapore, will it be absolutely unlikely to find a rarer Diadema sp. there too?

I think it is reasonable to be more circumspect and consider other possibilities.

To say that all black long-spined sea urchins "that everyone has seen on cyrene are D. setosum" is rather astonishing to say the least.

Especially since the ID key you refer to requires close examination of a dead urchin for a definitive ID.

In any case, I think ordinary people would be less interested in the exact species, and more interested in ecological roles, behavioural aspects and impact on human daily life.

From the opening remarks of the paper you quoted: Family Diademetidae "has been shown to have a very important role as reef grazers, particularly due to their size and numbers (Hughes et al. 1987).

"Species of the genus Diadema
Gray, 1825 have been reported to be the most widespread and ecologically important shallow
water genera of tropical sea urchins (Lawrence & Sammarco 1982; Lessios 1988; Birkeland 1989; Carpenter 1997)"

Grazing algae, these sea urchins prevent the algae from smothering corals.

So regardless of the species, Diadema play an important role in the reef.

Ivan said...

Moral of the story: We need more echinoderm experts! (Experts on echinoderms, not echinoderms who are experts)

Perhaps the next time we visit, we could obtain some specimens, get good photographs of them alive and dead from all angles, and send the specimens over for Dr. Lane or any other echinoderm expert to inspect.

Ron Yeo said...

Ria, first, I have to correct you that the test is NOT just refering to the dead skeleton. Even when it is alive, the globular shell that's covered with the spines is also called the test. So in other words, the ID is definitive on live specimens as well.

In fact, the first line of the abstract already states that "Test morphologies were examined for both living and denuded specimens".

Anyway, thought this is another good example of how wrong information could spread. Other people who read you previous comment will be misled unless they do some research on their own. But the problem is, many volunteers look up to you and may just take your word for it, just like the way you look up to Dr Lane. So I will really advise you to be more careful when you put up any info online in future :)

And please don't exaggerate my statment. I was just refering to the photos posted by the various people who visited Cyrene that day. That's what this whole string of comments are about, isn't it?

And if Dr Lane is saying those with orange anal rings we've been seeing is D. setosum, then I think something is seriously wrong. If he had told us to look out for those with bold blue lines and no orange anal ring, then I think that make more sense. We all hope to find more things on Cyrene, but then all the more we must make sure that we got our IDs correct. Or else, the surveys done are not going to be useful.

I fully agree that the ecological aspects are very important, but we must understand that every species perform different roles in different habitats. So the species itself is also important. And while the ordinary people need not know the exact species names, I think it's important to let them know the correct number of species that has been found to accurately portray the biodiversity. Or else some may assume it's not important to preserve all species, but just one species alone can perform the ecological role.

And of course, we must understand that the wrong info is not just spreading among the public, but could spread among volunteers and other scientists.

sits said...

Ron, I think you need to take a chill pill. Seriously.

When Dr. Lane mentioned the possibility that its another species, that's all he was highlighting: a possibility. If you are reading into that, then his statement could be interpreted as "at the end of the day, there is some contention over species distinctions, so don't take it for granted that what you see is what you think you see"

Your point that we should consult various sources is good and well, but sometimes who you ask can skew your answers as well.

The concept of species is not a stagnant one and should NEVER be viewed as such because things are constantly changing. Looking at the bigger picture, species are transient and they exist mainly as a stepping point in the infinite waltz of evolution.

I think we should stop arguing over this. Leave it to the readers to make their own judgment call. Anyone worth their salt will know that the unmoderated nature of the Internet means that there will be a propensity for error. Its been stated at several points that its a POSSIBILITY and we should leave it at that. As it is, this argument is starting to sound personal. If our aim as nature lovers is to spread the good word, then it is being sullied by this pointless bickering.

As I've said to you before, what matters to the public is that its there, its beautiful and for it to survive and continue being part of Singapore's amazing natural heritage, we need to conserve the habitat its found in.

If you still have issues with ID, take it offline.

Ron Yeo said...

Siti, like I've said to you earlier, if someone identifies Halophila spinulosa as Halophila ovalis, how will you feel? Why are we still surveying the types of seagrasses then, rather than just surveying the percentage cover etc of the seagrasses as a whole?

But anyway, I agree that it's useless to discuss this online any more. I've already posted the results of my findings, and corrected any wrong understanding of the relevant scientific terms.

Will leave it to the readers to do their own interpretation.

sits said...

Ron, like I've said to you already, there are species with obvious difference and species with more subtle differences.

If someone tried to pass off H. spinulosa as H. ovalis or vice-versa, then something is obviously wrong with them.

If however, people mistake H. ovalis and H. minor, I wouldn't get worked up about it because its something so similar with sometimes overlapping ID features - some people (myself included) are of the opinion that its actually one species with very plastic features.

To these people who mix them up, I'd say "Its my opinion that this is H. ovalis because of the following reasons, but whether you call it H. ovalis or H. minor, they are both pioneer species their ecological role is to make the habitat suitable for other species to colonize".

While its true that certain species fill very specialized ecological niches, there are broader implications that you can derive from just the genus of the animal alone. For example, most Diadema are algal grazers and an important part of a coral reef ecosystem.

I'm not saying that ID is not important, but you must realise that this particular example is getting particularly ridiculous. No one is forcing you or anyone else to accept that its D. savignyi, Dr. Lane stated it as a possibility and that's what it is.

If you think that you are correct in your ID based on your paper, then good for you. We can all take a leaf from your book in the self-confidence department. Rest in the knowledge that you are right and leave it at that. There is no need to disprove Dr. Lane or come down hard on anyone else who may have gotten their ID mixed up.

I will not be replying to any more of these posts, as far as I am concerned, the matter (which is such a non-issue in the first place) is closed. If you have a bone to pick with me, we will discuss it the next time we meet.


Ron Yeo said...

Aiyo, D. setosum and D. savignyi are species with obvious differences.

Anyway, this is getting ridiculous. I dun have a bone to pick with anyone here except Dr Lane. The suggestion that a sea urchin with all the characteristics of a D. setosum is possibly a D. savignyi to me is totally absurd, and that's why I'm so affected by it.

If anyone disagree with me, it's fine. But well, it's my habit to explain my case clearly to minimise any confusion.

Like I've said earlier, I think I've done my part, unless someone else bring up more issues then I'll have to explain things again. So please email me instead if you want to raise any issues so I don't have to flood this place.

From now, I'll just leave it to the readers to do their own interpretation.

matinggeckos said...

I think Dr. Lane will be disappointed that on the day of a new seastar record would also be the day that trigger this sad episode.

Dr. Lane is merely suggesting that the sea urchin might not be D. setosum. Pls bear in mind there are five classes within echinodermata. Dr. Lane is an echinoderm expert whose main strengths are probably on sea/brittle/feather stars, which is why chances are he'll:

1)recommend we seek a sea urchin expert to confirm ID (like what he did when I showed him a sea cucumber specimen)

2)the first to admit his mistake if he's wrong (which is what he did for the same sea cucumber specimen)

Dr. Lane has done nothing wrong here. There's no bone to pick. He is not myopic nor is Ria blind.

So what if he's wrong about the sea urchin? Pls remember much of what we know of Singapore's echinoderms are thanks to him and his team's work. He has spent much of his career deepening our local echinoderm knowledge. For that he deserves our respect, yes?

If there's any personal grudge involved, then pls keep it as that...personal. Pls don't drag Dr. Lane's good name into it.

Pls chill and see the big picture....save our shores.


Monkey said...

i agree with Robin!

We should be CELEBRATING a new record in our shores!

HURRAY BLack Evil STar whose scientific name and taxonomy I don't really care to know about because as a lay person I'm just excited at how our shores are thriving! YAY :)

Jeffrey said...

Interesting discussion. Hoorah!! for finding a "new" species on Singapore's shores - although .. "Black Evil Seastar"? :P

YC said...

WOW here's some intense chatfire.. looks like i missed the party

Ron Yeo said...

Yah YC, you've missed all the fun :P the chilli, the pepper, and lovely smell of gun powder... Haha