Magazine R858 Q & A David A. Shub After spending two postdoctoral years each in the laboratories of Jun-ichi Tomizawa in Tokyo and Dick Epstein in Geneva, David Shub joined the faculty of the Biology Department at the University at Albany, SUNY, where he has been ever since. For the past 17 years his lab has explored the self-splicing group I introns in bacteria and phages, with emphasis on their origin, distribution, and function as selfish elements. What turned you on to biology in the first place? It was a late conversion. As a child growing up in New York City, the wonderful diversity of nature, which attracts many children to biology, was not readily apparent (I think I had seen about four bird species in my first twenty years). School, where biology was presented as a set of unrelated facts that needed to be memorized for an examination, didn’t create a spark. In my twentieth year, while an undergraduate at Columbia University, three experiences were crucial. While introductory zoology was taught as a large lecture — and presented as an arbitrary collection of facts, just as in high school — all professors were required to conduct a discussion section each week with a small group of students. My section leader was Leslie Dunn, a distinguished fly geneticist who had worked with T.H. Morgan. The class dozed through these obligatory sessions, until the unit on genetics. This had been my favourite topic so far, involving little memorization and requiring us to do fun problems on blood groups and paternity suits. In our review session, Dunn seemed to wake up from his semester-long nap, becoming animated and enthusiastic. Instead of rehashing the material from the previous week’s lectures, he told us about sickle cell disease. It was a wonderful story, combining hemoglobin protein chemistry, Dark wings of desire Birds vary enormously in their use of the pigment melanin to colour their plumage but the variation between species and between sexes has been a puzzle to researchers. New work on the plovers, a diverse group of mostly ground-nesting birds which show highly diverse use of melanin, suggests that sexual selection during aerial displays is one cause of the pigmentation. Veronika Bokony and colleagues at the Szent Istvan University in Budapest and at the University of Bath, UK, report in the Proceedings of the Royal Society B in London (published online) a comparison of the wide variation in melanin- coloured plumage between different species of plover and other aspects of their lifestyle. The authors hypothesised that melanin-coloured plumage may be more common in species where males carry out aerial courtship displays compared with those using ground-based courtships. And the plovers include species that use both courtship behaviours. The authors thought that black plumage may help enhance the silhouette of the bird against the sky during an aerial display and thus increase the attention of ground-based females during the display. The results suggest that this is indeed the case. Birds with ground-based displays show much less melanin-coloured plumage compared with the males of species carrying out aerial displays. They looked at whether melanin coloration might help with camouflage or in displays to defend territories but found no link between melanin coloration and these two lifestyle aspects compared to the link with aerobatic courtship displays by the males. “Taken together, our results are most consistent with the sexual selection hypothesis, and suggest that melaninised plumage has evolved to enhance the aerial display of male plovers,” the authors report. Cutting an aerial dash, in black, seems to be the plumage key to attracting mates in this group of plovers at least. Black attack: Studies suggest areas of black plumage in plovers enhance the att- ractiveness of male birds in aerial courtship displays. (Photo: Oxford Scientific Films.)

Dark wings of desire

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MagazineR858

Q & A

David A. ShubAfter spending two postdoctoralyears each in the laboratories ofJun-ichi Tomizawa in Tokyo andDick Epstein in Geneva, DavidShub joined the faculty of theBiology Department at theUniversity at Albany, SUNY, wherehe has been ever since. For thepast 17 years his lab has exploredthe self-splicing group I introns inbacteria and phages, withemphasis on their origin,distribution, and function asselfish elements.

What turned you on to biologyin the first place? It was a lateconversion. As a child growing upin New York City, the wonderfuldiversity of nature, which attractsmany children to biology, was notreadily apparent (I think I had seenabout four bird species in my firsttwenty years). School, wherebiology was presented as a set ofunrelated facts that needed to bememorized for an examination,didn’t create a spark.

In my twentieth year, while anundergraduate at ColumbiaUniversity, three experiences werecrucial. While introductory zoologywas taught as a large lecture —and presented as an arbitrarycollection of facts, just as in highschool — all professors wererequired to conduct a discussionsection each week with a smallgroup of students. My sectionleader was Leslie Dunn, adistinguished fly geneticist whohad worked with T.H. Morgan. Theclass dozed through theseobligatory sessions, until the uniton genetics. This had been myfavourite topic so far, involvinglittle memorization and requiringus to do fun problems on bloodgroups and paternity suits. In ourreview session, Dunn seemed towake up from his semester-longnap, becoming animated andenthusiastic. Instead of rehashingthe material from the previousweek’s lectures, he told us aboutsickle cell disease. It was awonderful story, combininghemoglobin protein chemistry,

Dark wings ofdesireBirds vary enormously in theiruse of the pigment melanin tocolour their plumage but thevariation between species andbetween sexes has been apuzzle to researchers. Newwork on the plovers, a diversegroup of mostly ground-nestingbirds which show highly diverseuse of melanin, suggests thatsexual selection during aerialdisplays is one cause of thepigmentation.

Veronika Bokony andcolleagues at the Szent IstvanUniversity in Budapest and atthe University of Bath, UK,report in the Proceedings of theRoyal Society B in London(published online) a comparisonof the wide variation in melanin-coloured plumage betweendifferent species of plover andother aspects of their lifestyle.

The authors hypothesisedthat melanin-coloured plumagemay be more common inspecies where males carry outaerial courtship displayscompared with those usingground-based courtships. And

the plovers include species thatuse both courtship behaviours.The authors thought that blackplumage may help enhance thesilhouette of the bird against thesky during an aerial display andthus increase the attention ofground-based females duringthe display.

The results suggest that thisis indeed the case. Birds withground-based displays showmuch less melanin-colouredplumage compared with themales of species carrying outaerial displays. They looked atwhether melanin colorationmight help with camouflage orin displays to defend territoriesbut found no link betweenmelanin coloration and thesetwo lifestyle aspects comparedto the link with aerobaticcourtship displays by the males.

“Taken together, our resultsare most consistent with thesexual selection hypothesis, andsuggest that melaninisedplumage has evolved to enhancethe aerial display of maleplovers,” the authors report.

Cutting an aerial dash, inblack, seems to be the plumagekey to attracting mates in thisgroup of plovers at least.

Black attack: Studies suggest areas of black plumage in plovers enhance the att-ractiveness of male birds in aerial courtship displays. (Photo: Oxford Scientific Films.)