Incredible Creatures that Support Evolution?
Paleontologists and biologists continue to uncover animals past and present that exhibit amazing diversity. Some of them are so weird and unexpected, they are almost unbelievable. Usually, the news media are quick to tally up points for Darwin by explaining to lay people how they shed light on evolution. But in the “discovery” stage of science, before the “explanation” stage, maybe scientists need time to just assess what it is they are looking at.
- Imaginary feathers again: The big news this week was Haplocheirus sollers, another entry in the dinosaur-to-bird tale. This ungainly, slender, bizarre clawed thing was announced in Science magazine.1 The fossil, found in the Gobi Desert of China, has short arms, long claws, a long beak-like snout – and it’s said to precede Archaeopteryx by 15 million years.
The discoverers believe it essentially nails the case for birds evolving from dinosaurs – and the artists went right to work, adorning it with colorful feathers. Science Daily, for instance, alleged that Haplocheirus “Helps Solve Piece of Evolutionary Puzzle.” The BBC News went further, claiming that it really “solves evolutionary bird puzzle.” Strange thing, though – the original paper said nothing about feathers. The alleged feathers on the artwork appear to be completely imaginary – again (see 02/08/2006, 06/13/2007, 01/09/2008, 07/09/2008, 12/11/2009 bullet 2, and imbedded links). Richard Stone, writing about the find in the same issue of Science,1 talked a lot about feathers – but not in reference to Haplocheirus, where none were reported. In fact, both Stone and veteran “feathered-dinosaur” hunter Xing Xu in the original paper said very little about evolution, too. If anything, they indicated that the fossil confuses the alleged dinosaur-to-bird transition.
For one thing, this fossil is called a Maniraptoran, but this artificial class is defined as a group that includes both birds and dinosaurs. This could lead to charges of question-begging. Xu et al suggested that the fossil demonstrates that other basal Maniraptorans were not secondarily flightless birds, as had been supposed, but instead were incipient birds. The “convergence” explanation (01/26/2010), however, weighs heavily in the interpretation of this new dinosaur: “Haplocheirus preserves plesiomorphic morphological characteristics that confirm a basal position for Alvarezsauroidea within Maniraptora, demonstrating that these features of derived alvarezsauroids represent dramatic convergences with birds.” Plesiomorphic is a fancy word for convergently evolved.3 And the authors interpreted Haplocheirus as the more “primitive” maniraptoran simply because of its assumed earlier date than other members labeled “derived” (more evolved) due to their later dates. But read the paper’s final paragraph and see if it professes any confidence that this creature provides clear-cut evidence of dinosaur-to-bird evolution, as trumpeted by the press. Watch for how the words convergent, primitive and derived are employed:
Haplocheirus is the largest alvarezsauroid known from complete material (see SOM), and its basal phylogenetic position suggests a pattern of miniaturization for the Alvarezsauroidea, relatively rare in dinosaurs but convergently evolved in Paraves. Derived alvarezsauroids have a simplified, homogeneous dentition convergent with that of some extant insectivorous mammals, but Haplocheirus has recurved, serrated teeth and caniniforms that suggest carnivory was the primitive condition for the clade. The presence in Haplocheirus of only slightly reduced second and third manual digits and curved unguals with flexor tubercles on these digits implies that the hand was fully functional and Haplocheirus retained some grasping ability, unlike the presumably limited function of the greatly reduced lateral manual elements of Mononykus and Shuvuuia. The mediolaterally narrow McIII (metacarpal three) and the greatly shortened and slender McIV suggest that the extensive digital reduction and fusion seen in derived alvarezsauroids was already under way by the earliest Late Jurassic, proceeded from lateral to medial on the manus and, surprisingly, initially involved reduction in length of only McIV.
It sounds like they found another unusual dinosaur, with fully functioning arms and grasping claws, that did not announce it was trying to become a bird. That “suggestion” was imposed on the fossil by certain humans with a story in their minds. The words primitive and derived appear in the mind of the beholder; and when derived features appear on individuals deemed unrelated, the notion of convergent evolution is always available to rescue the story from the confusion (see 01/26/2010).
- Color me ginger: Another announcement this week also concerned dinosaur-bird evolution. The press, including BBC News, Live Science and Science Daily reported on a paper in Nature4 about scientists determining the color in alleged feathers of fossil specimens Sinosauropteryx and Confuciusornis. The press swamped the reader with implications that birds are evolved dinosaurs, employing phrases “birds of a feather” to emphasize the evolutionary interpretation. National Geographic was a little more reserved, stating that the study “may strengthen dinosaur-bird link.” It sported the largest artwork of the ring-tailed creature.
The placement of Sinosauropteryx in a dinosaur-to-bird transition, however, remains controversial (10/10/2005, 02/08/2006, 05/23/2007, 01/09/2008, 01/21/2009). Confuciusornis was already classed as a bird (02/21/2003). So the main argument in the paper regards whether melanocytes and their colors are diagnostic of feathers. Even if one accepts that point (although the bristly structures do not have the vanes and barbules of true feathers), and even if one accepts the date of and phylogenetic position of Sinosauropteryx, it is not clear to anyone why a dinosaur would grow feathers. Certainly it would indicate that the integumentary structures were not used for flying. The artist’s reconstruction shows a ground-dwelling creature covered in short, colorful fuzz. In addition, many other creatures have melanosomes that do not have feathers – like humans, zebras and cuttlefish (which have an even larger variety of chromatophores, including melanophores).
- Dino-gliders: becoming birds? Remember Microraptor gui, the strange biplane-like feathered bird-thing? (See 11/16/2005, bullet 2.) Many news sources, like CBC News, displayed the new model produced by a team of scientists who wanted to find out if the creature could glide. Their results were reported in PNAS.5 University of Kansas show partial success after some crash landings. The feature announced, “Researchers of microraptor shed light on ancient origin of bird flight.”
The assumption is that this creature reveals something about the “evolution of flight.” It appears clear that the creature could not walk on the ground very well with those long feathers on its hind limbs. Still, it is not clear that gliding squirrels, gliding lizards, or gliding monkeys are evolving powered flight. There were also, at that time, all the extremely agile and diverse pterosaurs that were not evolving into birds. Microraptor with its strange feather get-up may represent a bird in the process of losing powered flight, or an extinct animal among many extinct animals (cf. Anchiornis, 10/01/2009).
For evolutionists, Microraptor has become a focal point of the debate between tree-down (arboreal) and cursorial (ground-up) theories for the origin of flight (01/25/2008). The previous entry about melanocytes on Sinosauropteryx would support the latter; this entry argues the former. The artist reconstructions of Sinosauropteryx do not suggest anything close to a gliding animal, let alone a tree-climber. If David Alexander wants to promote Microraptor as favoring the arboreal theory, he will have to convince the Sinosauropteryx people that their fossil was not part of the flight story.
- Tyrannosaurus mama: Everybody loves the cuddly T-rex, at least the plush Christmas toy variety. Now, another “more primitive” tyrannosaur has been reported from New Mexico; see Live Science. Actually, the fossils of Bistahieversor sealeyi, as it was named, were discovered in 1998, but recent closer analysis shows it to be a distinct species. “To the untrained eye, Bistahieversor looks like most of its tyrannosaur relatives, but many subtle features, especially in its skull, set it apart,” the article said. That seems to indicate that none of the major tyrannosaur equipment was lacking in this fossil said to be 10 million years older than the terror of Jurassic Park. The concluding lines of the article indicate that a presumed evolutionary series is less than straightforward: “Bistahieversor shares a few characteristics with more advanced tyrannosaurs, like the T. rex, but also has many, more primitive features. The findings give the researchers insight into the evolution of this dinosaur linage [sic], helping them understand when particular features may have arisen.”
But “hey! what you callin’ primitive?” a street person might object. “The fact that Bistahieversor has a T.-rex-like snout, even though it is older, indicates that this feature is relatively primitive, Carr said, and it is not unique to more advanced tyrannosaurs.” This means that part of the “advanced” T-rex anatomy got demoted to primitive, just because it resembled the snout of an earlier tyrannosaurid dinosaur. What’s more, the article indicated that both primitive and advanced members of the family were contemporaries – only separated by presumed geographical barriers. Movie-goers, however, might remember that the designers of Jurassic Park did not find barriers very effective in keeping these giants from roaming wherever they wanted to go.
1. Jonah N. Choiniere, Xing Xu et al, “A Basal Alvarezsauroid Theropod from the Early Late Jurassic of Xinjiang, China, 148;Science, 29 January 2010: Vol. 327. no. 5965, pp. 571-574, DOI: 10.1126/science.1182143.
2. Richard Stone, “Bird-Dinosaur Link Firmed Up, And in Brilliant Technicolor,” Science, 29 January 2010: Vol. 327. no. 5965, p. 508, DOI: 10.1126/science.327.5965.508.
3. Plesiomorphyrefers to generalized similarity prior to a common ancestor – see 10/20/2006 for another example.
4. Zhang et al, Nature advance online publication doi:10.1038/nature08740 (2010); see summary on Nature News.
5. David Alexander et al, “Model tests of gliding with different hindwing configurations in the four-winged dromaeosaurid Microraptor gui,” Proceedings of the National Academy of Sciences early edition, January 25, 2010, doi: 10.1073/pnas.0911852107.
Evolutionists are fascinating. They are so clever at defending their worldview at all costs. Someone should scientifically study them as a social phenomenon.
Epilogue and Eulogy: The headline chosen for this entry was “Incredible Creatures that Support Evolution?” Some readers will recognize that as a takeoff on the instructive and visually-rich film trilogy from Exploration Films, Incredible Creatures That Defy Evolution (see 10/03/2009 Resource of the Week). The jovial, adventurous co-narrator of the series, David Hames, delighted viewers with his amusing introductions of each animal. We are sad to report that Mr. Hames lost his life in the Haiti earthquake of January 12. Exploration Films announced that he was trapped in the collapse of the Montana Hotel in Port-au-Prince while traveling to the poverty-stricken island to help make a film on children in need. Our hearts go out to his wife Renee, whose faith, she wrote, gave her a “great peace” about God’s sovereign will. David was an honorable, self-sacrificing Christian, whose legacy in the films will live on and continue to bless many.