Frogs!

June 30, 2011 • 5:31 am

by Greg Mayer

As an Everton supporter, I am loath to praise anything Mancunian, but Andrew Johnson, a Manchester zoology graduate, has a marvelous website on the Amphibians of Borneo, which was brought to my attention by Matthew (yet another praiseworthy Mancunian).

Ansonia leptopus (Bufonidae) by Andrew Johnson

The site contains excellent photographs of many species of Bornean frogs. What struck me most is the resemblance of many of the depicted species to Central American frogs, especially the Costa Rican ones with which I am most familiar. Our toad friend above reminds me of the gracile-limbed Central American toads of the genus Atelopus. (Superb photos of the various Costa Rican frogs mentioned can be found in Jay Savage’s magisterial The Amphibians and Reptiles of Costa Rica [see references] and at Costa Rican Frogs, a site I just discovered.). The following one is a more typical-looking toad, resembling various Central American Bufo.

Duttaphrynus melanostictus (Bufonidae) by Andrew Johnson

The following species resembles the Central American toad Bufo haematiticus in its cryptic forest-floor dress, but is in fact not a true toad, but a member of a different family.

Kalophrynus baluensis (Microhylidae) by Andrew Johnson

The resemblances between the Bornean and Central American frogs is a mixture of convergence (in this case, adaptation to the varied niches of tropical rain forest) and common ancestry (in some cases, a toad is a toad is a toad). Convergence is indicated when similar species are in different families, but it’s also possible within families. Both American Atelopus and Bornean Ansonia are members of the family Bufonidae (true toads), but their gracile form may have evolved independently from more squat ancestors (that’s why phylogenetic studies are so important for elucidating evolutionary phenomena– we need to know who’s related to who, and what the likely ancestral conditions were).

Here are several other of my favorites. The first resembles Central American Leptodactylus, especially pentadactylus.

Limnonectes ingeri (Dicroglossidae) by Andrew Johnson

Our friend above is named in honor of my esteemed colleague Robert Inger of the Field Museum, the dean of Bornean amphibian studies (see references below). The following species, in the same genus, Limnonectes, resembles various Central American Eleutherodactylus, a very species-rich genus with more than 40 Costa Rican species.

Limnonectes laticeps (Dicroglossidae) by Andrew Johnson

We’ll finish with some treefrogs, none of which are in the “true” treefrog family, Hylidae (which has many genera and species in Central America), but rather the Old World Rhacophoridae. The first resembles some of the the Central American Smilisca.

Rhacophorus cyanopunctatus (Rhacophoridae) by Andrew Johnson

The next resembles various Hyla.

Rhacophorus dulitensis (Rhacophoridae) by Andrew Johnson

And finally, a flying (actually gliding) frog; note the large webs. Some Costa Rican hylid treefrogs of the genus Agalychnis are capable of gliding, too.

Rhacophorus nigropalmatus (Rhacophoridae) by Andrew Johnson

A more academic site devoted to Bornean frogs, also beautifully illustrated and with a great range of useful information, is Frogs of Borneo, by Alexander Haas and Indraneil Das. The American Museum of Natural History is currently hosting a traveling exhibition entitled Frogs: a Chorus of Colors, featuring live (not preserved) frogs, which I saw when it was at the Milwaukee Public Museum, and is worth seeing if you’re in the New York area.

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Behler, J. and D. Behler. 2005. Frogs: A Chorus of Colors. Sterling Publishing, New York. (book to accompany the exhibition)

Inger, R.F. 1966. The systematics and zoogeography of the amphibia of Borneo. Fieldiana Zoology 52:1-402. (downloadable as pdf)

Inger, R.F. and R.B. Stuebing. 2005. A Field Guide to the Frogs of Borneo. 2nd ed. Natural History Publications (Borneo), Kota Kinabalu, Sabah, Malaysia. (available here)

Inger, R.F.  and F.L. Tan. 1996. Checklist of the frogs of Borneo. Raffles Bulletin of Zoology 44(2): 551-574. (pdf)

Savage, J.M. 2002. The Amphibians and Reptiles of Costa Rica | A Herpetofauna between Two Continents, between Two Seas. University of Chicago Press, Chicago.

World’s loudest creature (for its size)

June 30, 2011 • 5:05 am

Alert readers Diane G. and Ray P. called my attention to a new paper in PLoS ONE by Soeur et al. that reveals the loudest known creature for its size on Earth.

What is it?  It’s a water boatman of the species Micronecta scholtzi. These are in the Hemiptera (“true bugs,” remember?).  It’s tiny—only 2 mm long (the size of Lou Jost’s orchid)—and inhabits streams in Europe. Here’s one:

What’s the big deal?  These insects produce the loudest sound per unit length of any known species on Earth. Scientists captured some in a river in Paris and recorded them underwater in the lab using a hydrophone.  Only the males make noise, a clue that the song serves a sexual function.

How loud are they? The authors note: “SPL [sound pressure level] values of M. scholtzi were compared with the values reported for 227 other species (2 reptiles, 3 fishes, 24 mammals, 29 birds, 46 amphibians and 123 arthropods) collected from the literature (Table S1).

The song consists of three parts, and the third, the loudest, can be as large as 105 decibels! That’s as loud as a power mower from three feet away, and a level that, if inflicted constantly, could cause permanent hearing loss.

Is it really the loudest animal on earth?  Yes, if the volume is scaled by a measure of body size (length). As the article notes:

. . .  the most striking feature of the song is its intensity. The song can be heard by a human ear from the side of a pond or river, propagating across the water-air interface. Estimating the sound intensity at a distance of one metre reveals a value of ~79 dB SPL rms. When considering peak values, i.e. the loudest part of signal, the intensity can reach 100 dB SPL. Whilst these values are far below those estimated for large mammals such as dolphins, whales, elephants, hippos, or bison, when scaled to body size, M. scholtzi has the highest ratio dB/body size. Even if such comparison might need to be adjusted with corrections taking into account different recording methods and conditions, M. scholtzi is clearly an extreme outlier with a dB/body size ratio of 31.5 while the mean is at 6.9 and the second highest value is estimated at 19.63 for the snapping shrimp S. parneomeris. This water bug might be the exception that proves the rule that stipulates that the size and the intensity of a source are positively related. This departure from the rule is apparent within the group of stridulating animals. In this sub-sample, M. scholtzi is identified as an extreme outlier. No other recorded animals rival M. scholtzi. Two other arthropods were also identified as outliers; the Australian miniature cricket C. canariensis [27] and the Praying Mantis M. religiosa [28].

Well, what’s the real loudest animal on earth? If you don’t scale by body size, it is a whale and a monkey in the aquatic and terrestrial realms, respectively. The National Zoo says this:

Blue whales’ low-frequency pulses are as loud as 188 decibels—louder than a jet engine—and can be detected more than 500 miles away. On land, the loudest animals are howler monkeys, whose howl can be heard three miles away.

How and why do they make this noise? The males rub their penis against their abdomen. The authors theorize that “runaway sexual selection” due to competition by males for females has made the song so loud. But there are other forms of sexual selection not mentioned by the authors, like “sensory exploitation” (females pre-adapted to respond to such songs), that could also explain the evolution of such loud songs. There are many forms of sexual selection and it’s very hard in a given case to figure out which has operated.

You can hear the sounds of these insects by clicking on a BBC Nature piece, “‘Singing penis” sets noise reord for water insect.

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Sueur J, Mackie D, Windmill JFC, 2011. So small, so loud: Extremely high sound pressure level from a pygmy aquatic insect (Corixidae, Micronectinae). PLoS ONE 6(6): e21089. doi:10.1371/journal.pone.0021089

Eyes from the deep past

June 29, 2011 • 11:15 pm

by Matthew Cobb

[I just posted this over at z-letter.com – it’s reposted here with Jerry’s permission]

The most dramatic early eyes known up to now have been, not surprisingly, the calcite eyes of trilobites. These mineral lenses, formed into a compound eye, lend themselves to fossilisation, plus there are millions of fossilised trilobites lying around in rocks. In the latest issue of Nature, there is a dramatic description of an incredibly tiny fossil from Australia that reveals that at least one organism from the early Cambrian – 515 MY ago – had eyes that were incredibly complex and modern.

The work was carried out by a group from Australia (with help from the Natural History Museum in London), led by Michael Lee and John Paterson. They studied rocks from the Emu Shale in Kangaroo Island in South Australia. This is a famous layer of shale which contains some exceptionally preserved organisms, and is a useful comparison with the Burgess Shale in Canada and Chenjiang in China.

The researchers found a number of isolated fossilised eyes that had apparently come from some kind of arthropod. They are about 7 mm long, are curved, and are composed of up to 3,000 individual lenses or ‘ommatidia’. They are not made of calcite, and they are not from a trilobite. They are incredibly beautiful. The eye of the robber fly is included for comparison. These were NOT from a fly! They are from a marine organism!

a–d, Three fossils of compound eyes from a large arthropod from the Emu Bay Shale, South Australia (a–c), shown in similar hypothesized orientation to the compound eye of a living predatory arthropod, the robberfly Laphria rufifemorata (d; anterior view of head). All fossil eyes have large central ommatidial lenses forming a light-sensitive bright zone, b, and a sclerotized pedestal, p. Because the fossil eyes are largely symmetrical about the horizontal axis, it is not possible to determine dorsal and ventral surfaces, and thus whether the eyes are left or right. All fossils are oriented as if they are left eyes (medial is to the left of the figure). In b there is a radial tear (white line) with the top portion of the eye displaced downwards to overlie the main part; extensive wrinkling causes some central lenses (arrow) to be preserved almost perpendicular to the bedding plane.

The fossilised eyes were all about the same size, suggesting they had all come from adults. Sadly, there are no clear animal remains associated with them. They presumably became separated from the body either because the animals were predated in some odd way (predators spitting out the eyes?) or because they are in fact the cast of the organism as it grew in size. They say:

“One possibility is that the fossils reported here are of previously shed corneas. The corneal surfaces of living arthropods detach during ecdysis and remain loosely connected to the rest of the exuvia; moulted corneas might be more prone to decay and thus more susceptible to early diagenetic mineralization (in this case phosphatization) than complete eyes attached to intact organisms.”

The fine detail of the fossils made it possible to calculate the precise distance between the ommatidia. Note that the lenses are hexagonal, just as in modern arthropods:

Cambrian arthropod eye. a, Entire specimen showing the positions of close-ups in c and f. b, Relief-map three-dimensional reconstruction of a. c, Close-up of large ommatidial lenses in the bright zone, with white line and numbers referring to the cross-section shown in e. d, Relief-map three-dimensional reconstruction of c. e, Cross-section through four large lenses indicated by the white line in c; numbers refer to individual lenses represented by concavities. f, Close-up of small marginal lenses, with white line and numbers referring to the cross-section shown in h. g, Relief-map three-dimensional reconstruction of f. h, Cross-section through four small lenses indicated by the white line in f; numbers refer to individual lenses represented by concavities.

The authors then go on to look at the optics of these eyes, in terms of the density of the ommaditidia. And report that this kind of complexity and density has previously been found only in the the Ordovician, around 40 MY later.

So – what animal do they belong to? They are too small to be from everyone’s favourite Cambrian predator, Anomalocaris. The authors reckon that they could be from a bivalve arthropod found in the Emu Bay shale called Tuzoia:

The large, unnamed Tuzoia species from the Emu Bay Shale has stalked compound eyes that are ovoid to round and 6–9 mm in diameter: very similar to the fossil eyes described here. However, no detailed structure of the visual surface is preserved in the articulated eyes of Emu Bay Shale or Burgess Shale Tuzoia specimens.

Here’s a picture of Tuzoia:

Reconstruction of Tuzoia.

The authors conclude:

The specimens described here represent the first microanatomical evidence confirming the view that highly developed vision in the Early Cambrian was not restricted to trilobites. Furthermore, in possessing more and larger lenses, plus a distinct bright zone, they are substantially more complex than contemporaneous trilobite eyes, which are often assumed to be among the most powerful visual organs of their time. The new fossils reveal that some of the earliest arthropods had already acquired visual systems similar to those of living forms, underscoring the speed and magnitude of the evolutionary innovation that occurred during the Cambrian explosion.

“The Undefeated”: Palin biopic

June 29, 2011 • 12:44 pm

Speaking of hopelessly insane presidential candidates, did you know that in only two weeks AMC theaters will release a Palin biopic/documentary, “The Undefeated”?   It is, of course, dreadful, but some think this is set to bolster a presidential run.  My own theory (which is mine) is that Palin will sit back until internecine squabbling among Republicans leaves them with no clear front-runner, and then she’ll boldly throw her hat into the ring.

Here’s one (negative) review of “The Undefeated” in The New York Post.  Here’s a partial clip from Sean Hannity with analyses by Monica Crowley and Sandra Smith, both agreeing that this seems like pre-presidential hype.

But for more hilarity, check out the way Rotten Tomatoes (my favorite movie-rating site) classifies the movie (h/t to reader Adrian for this):

Evangelicals, evolution and atheism: the 2011 Pew Foundation survey

June 29, 2011 • 5:32 am

This is a guest piece by reader Sigmund, who read the entire 100-odd page Pew survey. My thanks for his written take on it.

Compared to most developed nations, the proportion of evangelical Christians in the USA is far higher. In 2004 they comprised 26.3% of the population. At the same time, the level of acceptance of the theory of evolution is significantly lower. The question of whether there is a direct connection between evangelicals and the rejection of evolution has been difficult to quantify, however, since most surveys to date have not separated specific religious subgroups.

This issue has now been addressed in a new survey released by the Pew Research Forum on Religion and Public Life, who polled the opinions of evangelical leaders attending last year’s Lausanne Congress on World Evangelization.

A quick background on the Lausanne Congress is in order. The number of evangelical Christians has risen worldwide from about 80 million in 1910, 90% of whom lived in the US or Europe, to over 260 million today—the majority of whom live outside Europe or the USA. The first international congress of worldwide evangelical leaders was organized by Billy Graham in Lausanne, Switzerland in 1974, followed by the second in 1989 in Manila.

The current survey involved attendees of the third convention, which took place in Cape Town, South Africa, in October 2010. This congress brought together over 4000 evangelical leaders from across the globe in numbers representative of the proportion of evangelical Christians in each region. Viewing this as the perfect opportunity to gauge what the leaders of the worldwide evangelical community feel about a wide variety of contentious issues, the Pew Research Center devised a questionnaire that was sent to all attendees, the majority of whom completed it.

The full survey summarizes evangelical opinions on a wide variety of topics, and is available from this link. Here I’ll concentrate on the results of a subset of questions of special relevance to the readers of this site.

Evangelicals and Evolution

First, and probably of no surprise to anyone, is the result of the question regarding acceptance of the scientific theory of evolution. The survey posed the question:

“Which statement comes closest to your own views?” –  the options being:

  1. Humans and other living things have evolved over time due to natural processes such as natural selection.
  2. A supreme being guided the evolution of living things for the purpose of creating humans and other life in the form it exists today.
  3. Humans and other living things have existed in their present form since the beginning of time.

In other words the choices are evolution, intelligent design of the Michael Behe variety, and standard creationism. It is important to note that the Pew foundation used a wording for the evolution option that, unlike some previous surveys, doesn’t specifically exclude a role for God: for instance, someone who believes that God set up the laws of nature and that biological evolution is just one of the consequences of these laws should answer option A.

What proportion of evangelicals accept the scientific theory of evolution?

The answer is 3%

Almost half (47%) of respondents opted for traditional creationism, while 41% chose intelligent design. Not exactly testament (ahem) to the success of BioLogos in convincing evangelicals to accept biological evolution. Bearing in mind that surveys of this type usually have a margin of error of several percentage points (surveys of atheists occasionally show a similar percentage answering that they believe in God!), one can read this result as a unanimous rejection by this community of the scientific consensus on biological evolution.

To put the 3% figure in perspective, it is the same as the percentage of evangelicals who answered that it is not “essential to follow the teachings of Christ in one’s personal and family life”: pretty much the defining feature of evangelical Christianity. Furthermore, the 3% figure for support of evolution by evangelicals was consistent across all geographic regions.

BioLogos, in trying to convince evangelical Christians to accept evolution while keeping their religion, may be tacking an almost insurmountable problem. Rejection of evolution is not simply a theological side issue in evangelical Christianity, but appears to be a defining feature.

The Problem of Atheism

Evangelical Christianity, as a whole, tends to more prevalent in countries with higher levels of religiosity. Regions such as the USA, South America and sub-Saharan Africa have large numbers of Evangelical Christians in contrast to Northern Europe.  Most evangelicals attending this congress, then, will have come from countries with a low percentage of atheists in their population.

This makes it all the more surprising that the number one issue seen as a threat to Evangelicism was “The influence of secularism” (secularism and atheism/non belief in God is frequently used within the survey as meaning the same thing). 71% of evangelicals saw this as a major threat while 20% viewed it as a minor threat. In comparison, the influence of Islam is seen as a major threat by 47% of evangelicals and government restrictions on religion by 22%.

Taking these figures into account, we can perhaps see why atheists figure prominently in another survey result—the views of other religious traditions.

Atheists are the number one most hated group by evangelicals, 70% of whom say they have an unfavorable opinion of atheists, although Buddhists, Hindus and Muslims (65%, 65% and 67% unfavorable, respectively) are close behind.

Curiously, though, when asked about how they perceive the friendliness of other religious groups towards evangelicals, only a minority of evangelicals (45%) view atheists as unfriendly, with most  perceiving atheists as either neutral (49%) or friendly (8%). The figures for the perceived friendliness of atheists are very similar to those  of Jews, Buddhists and Hindus—Muslims were the exception, with 69% of evangelicals perceiving them as unfriendly towards evangelicals.

So, compared to other non Christian groups, atheists are not perceived as particularly unfriendly towards evangelicals, yet we are by far the most hated group. Perhaps it’s our inherent tendency towards violence that is the problem (remember Stalin!)

Apparently not. The survey asked whether some religions were more prone to violence than others. Despite atheism being one of the possible answers in this question, not a single evangelical answered that atheism was prone to violence. Considering that some of the evangelicals at the conference will have come from countries in Northern Europe with atheist majorities, they would have been aware if the gradual drop in Northern European religiosity resulted in believers getting carted off to the killing fjords.

So, on to the final mention of atheists in the survey.

Guess who evangelicals see as the top priority for evangelization?

Yes! It’s us again!

73% of evangelicals view the non-religious as the top target for evangelization.

This compares to 59% voting for Muslims and 27% for Jews.

Unfortunately, the survey only hints at how this evangelization process might proceed. When asked about their missionary position evangelicals were firm: the vast majority (86%) viewed using local missionaries, rather than sending in outsiders, to try to convert people of a different belief.

In terms of converting atheists, though, this seems problematic.

Evangelicals trying to convert atheists would need a missionary who is an atheist yet agrees with them on many core issues. This missionary would need to have an almost irrational hatred for outspoken atheism, a love of religious belief and an almost uncanny ability to get up atheists’ noses. Where on earth will they find someone like that?

OK, now that we’ve covered the serious stuff in the survey, we can look at the answers to the set of humorous questions that some comedian on the staff of the Pew foundation slipped in for a laugh.

First, remember how everyone agreed that Harold Camping was a lunatic for telling everyone who would listen that Jesus was about to return to Earth to rapture up to heaven a subset of believers,  leaving the rest of us to suffer a seven year period of tribulation? Well apparently ‘everyone’ did not include the evangelical community, an overall majority of whom answered that Jesus will return during their lifetimes (44% say probably and 8% say  he will definitely return) and that the rapture and tribulation will occur (61%  agree).

There also appears to be a curious hatred for “Yoga as a spiritual practice” amongst evangelicals, with 92% saying that it is incompatible with evangelical Christianity. One suspects that an intervention by Chris Mooney and Elaine Howard Ecklund is required (these evangelicals are clearly interpreting the word “spiritual” the wrong way, aren’t they?)

Of particular interest in this survey is the direct connection many of the leadership of the evangelical community appear to have with God Himself.

“Nearly all the evangelical leaders surveyed (94%) say they have received a direct answer to a specific prayer request at some point in the past.”

Is God Confused?

Despite this direct line to the top, there seems to be a curious variation in what God is telling different leaders, especially when you ask evangelicals who come from North America and Europe (Global North) compared to evangelicals from the Middle East and Africa (Global South). For instance God seems very confused about alcohol.

“A majority (73%) of the leaders from the Global North consider alcohol consumption to be compatible with being a good evangelical Christian. By contrast, a similarly large majority of the leaders from the Global South (75%) say alcohol consumption is not compatible with being a good evangelical.”

And that’s not all.

Despite 84% of worldwide evangelical leaders saying that homosexuality should be discouraged, a majority of evangelical leaders (51%) from South and Central America answered that homosexuality should be accepted by society.

What’s more, there appears to be a marked difference in views on how women should be treated.

“Among U.S. leaders, 44% agree women should stay at home, while 53% disagree. Leaders in Europe, however, reject the idea of women staying at home by a more than two-to-one margin, 69% to 28%.”

and

“European leaders (62%) and North American leaders (54%) are especially likely to reject the idea that a wife must always obey her husband. On the other hand, upwards of 60% of leaders from sub-Saharan Africa, the Middle East-North Africa and the Asia-Pacific region agree that a wife must always obey her.

The secularist might suspect that major differences in fundamental beliefs (acceptance of homosexuality, treatment of women, whether it is acceptable to drink alcohol) might be due, not to revelatory instructions from on high (after all, all of these folks purport to believe in the same Scripture), but to underlying social conditions such as the level of education of the population, whether there is an adequate social welfare and healthcare system in place, and the value placed on knowledge, equality and freedom of expression.

Summary

In conclusion, we can look at this report as an important and informative study of a group we need to take seriously due to their numbers and influence. Harold Camping gets mocked by TV networks and ignored by those in power, while Rick Warren gets a slot on the Presidential podium.

While evangelicals’ opinions on social matters vary depending on the social norms of their locality, we find that rejection of evolution by evangelicals is universal. Finally, we note that the greatest perceived threat to evangelical Christianity is the effect of the non-religious.

Well, at least they got that one right!

 

The second disease eliminated on Earth

June 29, 2011 • 4:22 am

These are true triumphs of human endeavor: we’ve completely eliminated two diseases from the face of  the Earth.

You know one of them already: smallpox, declared defunct in 1979.  But what’s the other?

As The New York Times reported yesterday, it’s rinderpest, a word that means “cattle plague” in German.  But it didn’t just kill cows: it affected many artiodactyls, including giraffes, buffalos, and gnus (wildebeests).  It was—the last case was reported a decade ago—caused by a virus that’s spread largely by contaminated water, had an almost 100% mortality rate in unexposed herds, and is thought to be closely related to the measles virus, which mutated to rinderpest about a thousand years ago.

Next week the disease will officially be declared an ex-virus, singing in the choir invisible.

The story of how it was vanquished is a fascinating mixture of history, testifying to the diligence of politicians, immunologists, and, especially, the field workers who did the dirty work of vaccination:

“The way we previously did it was really mindless,” said Dr. Peter L. Roeder, who directed the final eradication drive after working on the two earlier ones. “We’d get up before dawn to drive long distances. We’d be wrestling the animals to the ground, it’d get stinking hot, and pretty soon the locals would get fed up and walk away.”

The cattle were nervous and hard to handle, and no wonder, he said: They lived day and night with their owners and now were being roped and tackled by white men wearing khaki and reeking of unfamiliar soaps and deodorants.

“But someone local, dressed as a local, with mutton fat rubbed in his hair, could walk among them and stick in a needle and barely be noticed,” Dr. Roeder said. “We’d be lucky to get 20 percent immunity in a herd; our local guys could get 90, 95 percent.”

Here’s a short video describing the battle: