Review of 2014

I am still far from being a regular blogger (and I have no issue with that), but I have at last broken the trend of increasingly shirking the blog with each passing year. On the other hand, I posted significantly less on the Tumblr in 2014 than in 2013. (There was, in fact, a greater absolute number of posts on the Tumblr last year, but the average concentration of posts per month was far lower.) This was, at least in part, due to the fact that I was working on a story arc for the comic over the summer months, something I have not done since the first year of this blog. The basic concept for that story had been drifting in my mind for at least a couple years, so it was good to get it out of my system. While that translated to my falling behind on answering Tumblr questions, it was also an important contributor to last year's increased post count on here. Circumstances permitting, there is more to come.

In retrospect, I did quite a large amount of traveling over the past year (to New York, Arizona, Tokyo, and Ohio), which further added to the blog post boost. In spite of long periods of stagnation on the comic (per usual), I continued to receive fan art, for which I am immensely grateful. Last but not least, I did not forget about April Fools'.

Cover image for the "Turn to Stone" storyline.

What's new with maniraptors? I don't yet foresee a year where the answer will not be "Lots!" In January, new specimens of Hongshanornis, Pengornis, and (the possibly raptorial) Bohaiornis were described. A review on bird behavior in the fossil record was published. The enigmatic paravian Zhongornis, known only from a juvenile specimen, was suggested to be a scansoriopterygid, but there are reasons to be suspect of this result. A hoatzin from the Miocene of Kenya was reported. Powered flight was found to have driven the reduced genome size of birds. Falcons were discovered to pursue prey using visual motion cues. New studies came out on the benefits of V-formation flight, the aerodynamics of Microraptor, and timing the origin of neornithines. Newly-named maniraptors included the enantiornithines Parvavis chuxiongensis, Parabohaiornis martini, and Longusunguis kurochkini, the troodont Gobivenator mongoliensis, the Eocene hoatzin Protoazin parisiensis, and the Paleocene avialan Australornis lovei.

The skull of Gobivenator mongoliensis, from Tsuihiji et al., 2014.

In February, mutualism was documented between green-backed firecrown hummingbirds and cryptogamic plants. The pale eyes of jackdaws were found to function in deterring intruders. Chickens with artificial long tails were used to study how non-avian dinosaurs might have walked. Brown thornbills were reported to mimic different alarm calls in response to different threats. Isotopic evidence was used to support the notion that Gastornis, frequently portrayed as a fearsome predator, was probably herbivorous. New studies came out on avian forelimb development, the evolution of melanosomes in maniraptors and other feathered dinosaurs (which also discovered that the feathers of Caudipteryx may have been black), the aerodynamics of diving flight in peregrine falcons, the relationship between avian ecology and caudal skeletal morphology, and the efficiency of lift generation in common swifts.

Experimental design of chicken walking study, from Grossi et al., 2014.

In March, great tits were reported to deliberately withhold information from competitors. The mechanisms of color production in the plumage of male Lawes's parotia were described. Retaliatory behaviors by avian brood parasites were found to be promoted by plastic defensive behavior in their hosts. Another study showed that there are circumstances under which a host can benefit from brood parasites. The reconstruction of colors from fossilized pigments that has been a growing field these past few years was questioned, suggesting that supposed fossil pigments are really traces of bacteria. There were multiple presentations on both sides of this controversy at the SVP conference later in the year, so little doubt there will be much more to say about this subject in the near future. New studies came out on the phylogenetic position of the spotted wren babbler, causal understanding in New Caledonian crows, and the extinction of moas. Newly-named maniraptors included the Pliocene penguin Eudyptes calauina and the long-awaited large caenagnathid Anzu wyliei, too late for the oviraptorosaur-heavy 2013 but very much welcome.

Skeletal reconstruction and fossil material of Anzu wyliei, from Lamanna et al., 2014.

In April, visual effects of bowers built by great bowerbirds were described. The interpretation of Archaeopteryx as having had elongate covert feathers was disputed. Field observations of the rare black-throated blue robin were published. New specimens of Yanornis were described. New studies came out on the diversification of hummingbirds, the growth of Gargantuavis, the ability of birds to learn structural efficacy of nesting material, the understanding of social relations among common ravens, quantification of feather wettability, and the running performance of bar-headed geese under low oxygen conditions.

Phylogeny of hummingbirds, from McGuire et al., 2014.

In May, flexible alarm mimicry by fork-tailed drongos was published (which had been previously filmed in the 2013 BBC documentary series Africa). The braincase of Nothronychus and the jaw musculature of the laughing kookaburra were described, as was a new specimen of Zhouornis. Long-axis rotation was found and quantified in avian bipedal locomotion. An extremely well-preserved griffon vulture fossil specimen with soft tissues was reported. Pseudaptenodytes macraei was redescribed. Pumiliornis was found to have eaten pollen. Hoopoe eggshells were discovered to enhance adhesion of symbiont-carrying secretions. New studies came out on the function of therizinosaur claws, paleognath phylogeny, the development of feather asymmetry, the evolution of WAIR, and the post-fledging dispersal of king penguins. Newly-named maniraptors included the confuciusornithiform-like Cretaceous pygostylian Evgenavis nobilis, the Cretaceous euornithine Tianyuornis cheni, the Eocene gruiform Galligeranoides boriensis, and the possibly scansorial enantiornithine Fortunguavis xiaotaizicus.

Virtual cast of exceptionally-preserved griffon vulture fossil, from Iurino et al., 2014.

In June, "Saurornitholestes" robustus was reevaluated as a troodont. Eurasian jays were found to use acoustic cues to pilfer the caches of others. The Wakatobi flowerpecker was re-split from the gray-sided flowerpecker. The possibility of finding carotenoid pigments in feathers preserved in amber was evaluated. New studies came out on the bite performance of loggerhead shrikes, the identification of Euryapteryx moa chicks, the population fluctuations of passenger pigeons, the genomic landscape underlying the carrion-hooded crow complex, the evolution of avian egg patterns, elaborate signals in tanagers, and carotenoid-pigemented plumage, the leap and strike kinetics of barn owls, and the development of zygodactyl feet. Newly-named maniraptors included Spizelloides, a new genus for the American tree sparrow.

Wakatobi flowerpecker (right column) compared to gray-sided flowerpecker (left column), from Kelly et al., 2014.

In July, an excellent new specimen of Archaeopteryx was described. (This paper additionally coined the name Pennaraptora for the least inclusive clade containing oviraptorosaurs and paravians, a term we had been sorely in need of.) Anatomical change through ontogeny in chickens was documented in detail. Ichthyornis was reported from Mexico for the first time. New material of Itemirus was described, supporting the idea that it was a dromaeosaurid, though skepticism exists about this assignment and conclusion. New material representing very large specimens was also described for Palaeeudyptes. The oldest known avian eggshell, hailing from the Early Cretaceous, was reported. New studies came out on the wing dynamics and efficacy of hovering hummingbirds, the vocal repertoire of African penguins, and the evolution of the modern avian tail. Newly-named maniraptors included the pelagornithid Pelagornis sandersi (one of the largest known flying birds), the microraptorian Changyuraptor yangi, and the Miocene duck Bambolinetta lignitifila (formerly a species of Anas), while the Miocene stem albatross Chenornis was sunk into Plotornis.

New specimen of Archaeopteryx, from Foth et al., 2014.

In August, sustained miniaturization in avian evolution was supported. Aerial righting behavior was documented in juvenile chukar, suggesting yet another possible function for incipient wings. No evidence for attraction to shiny objects in magpies was concluded by one study. New studies came out on tinamou phylogeny, the evolution of migration in New World songbirds, sweet taste perception in hummingbirds, and the semilunate carpal in theropods, and the coevolution of the avian caudal skeleton and tail feathers (with implications for reconstructing the tail feathers of extinct birds). Newly-named maniraptors included the enantiornithine Grabauornis lingyuanensis.

Aerial righting behavior in juvenile chukar, from Evangelista et al., 2014.

In September, social transmission of tool use was documented in Goffin's cockatoos. The Rodrigues solitaire was digitally reconstructed. Anchiornis and Sapeornis were argued to lack sterna. The elaborate tail plumage of peacocks was found to not hinder their ability to take off. New studies came out on the evolution of avian wrist bones and rates of evolution in coelurosaurs (including maniraptors).

Evolution of wrist bones in theropods, from Botelho et al., 2014.

In October, great antshrikes were reported to have learned to use tools in order to prey on invasive land snails. The Eocene paleognath Palaeotis was restudied. Long-billed hermit hummingbirds were found to have sexually dimorphic bills used as weapons by the males. Extreme nomadism in banded stilts and prenatal learning in superb fairy wrens were documented. The skull anatomy of Haplocheirus was described. Male great bustards were shown to consume more poisonous foods than females do. Running birds were discovered to prioritize leg safety on uneven terrain. New studies came out on cotinga phylogeny, the diversification of crown-group rails, the aerodynamics of Microraptor (again), ontogenetic scaling in the hindlimb muscles of greater rhea, the expansion of ostriches into India, and the function of wing tucks in steppe eagles. Newly-named maniraptors included the enantiornithine Eopengornis martini, the Cretaceous euornithine Iteravis huchzermeyeri, and the basal avialan Jeholornis curvipes (the holotype specimen of which was initially going to be described in a different manuscript).

Long-billed hermit hummingbird, photographed by Kradlum, licensed.

In November, the cranial anatomy of Erlikosaurus was described. Brood parasitism was elicited in zebra finches by nest destruction. The osteohistology of Hesperornis and pygoscelid penguins was compared. Juvenile cinereous mourners were reported to mimic toxic caterpillars. New specimens of Scaniacypselus were published. New studies came out on the evolution of avian egg shape, the microbiome of New World vultures, and the function of cassowary casques. Newly-named maniraptors included the Pliocene vulture Aegypius varswaterensis, the Cretaceous euornithine Gansus zheni (which, as it turns out, is probably the same as Iteravis), and the Sulawesi streaked flycatcher (Muscicapa sodhii).

Juvenile cinereous mourner (left) and contemporaneous toxic caterpillar (right), from Londoño et al., 2014.

In December, a massive paper drop landed on our heads as the numerous findings of the Avian Phylogenomics Project were simultaneously published. Hummingbirds were found to control hovering flight by stabilizing visual motion. New cultural traditions were experimentally introduced to great tits. The endocranium of Conchoraptor was redescribed. Bird tracks were reported from the Cedar Mountain Formation for the first time. Spontaneous analogical reasoning in crows was documented. The white-faced ground sparrow was split from the Prevost's ground sparrow. New material of Microraptor (used a couple years ago to reconstruct its plumage coloration) and Caenagnathasia was described. New studies came out on wing versus leg investment in birds and the anatomy and ontogeny of paleognath hindlimbs.

Phylogeny of extant birds based on whole genome analysis, from Jarvis et al., 2014.