ESRM 456

January 8, 2018 | Author: Anonymous | Category: Science, Biology, Ecology
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ESRM 456 Biology and Conservation of Birds John Marzluff 123E Anderson 206 616 6883 [email protected]

Course Web Page • Web site – http://courses.washington.edu/vseminar • Follow links to ornithology (field and lecture)

• Class email list – Important to monitor your u. account for announcements related to class notes, etc. • [email protected]

Assignments and Grading • CRITICAL THOUGHT EXERCISES (100 Points). Throughout the quarter I will provide materials for you to evaluate (e.g., conservation plans, scientific papers, etc) and discuss. Each student will turn in a 1 page summary of their review and discussion. There will be 5 assignments worth 20 points each. • MIDTERM EXAM (100 Points). My exams include long essay and discussion problems. The midterm will include all material covered up to that point and will be a take-home exam. • FINAL EXAM (DEC 12, 830am, Wink 201; 200 Points). The final exam will be comprehensive. • RESEARCH PAPER (due December 2; 100 Points). You can choose the topic of your choice that involves bird biology or conservation and write a research paper that reviews and synthesizes the relevant scientific literature. Pose questions for future study. No more than 5 pages in length (double spaced), not including references or tables/figures.

Why Birds? • • • •

Taste great Look nice Culturally important Useful in sport and work • Interesting and everywhere • Need active conservation

Birds are Tasty

Subsistence Among Native Peoples

Harvest of arctic birds: early 20th century

Egging Starting in the 1840s… “Doc Robinson came west to start a theatre company but soon discovered more money was to be made by stealing. He plundered eggs from the common murres nesting at the Farallons and sold them for $1.75 a dozen. The Farallon Egg Company was soon formed and every May through July ten to fifteen men gathered, packaged, shipped and sold the eggs. During the early days 600,000 eggs were taken per year; an estimated 14 million eggs were removed in a 40-year period. The original murre population of a half million was reduced to several thousand by the turn of the century.” From, M. Ellis. History of the Farallon Islands: an essay

Egging on SE Farallon Island, California

Egging

Laysan & Black-footed Albatross eggs being harvested on Midway Island. Early 20th century.

Feathers are Pretty and Useful

Check out Thor Hanson’s 2011 book “Feathers”

Birds are Good Hunters

They are Reliable

Raven saving Elijah

Swiss Army with carrier pigeons Early 19th century pigeon

• They are diverse and everywhere – 9700 species in world – 650 in US and Canada

Hawaiian Drepanids--Splendid Isolation • Adaptive Radiation – Single ancestor, radiation in bill shape to exploit variety of resources

• Convergent Evolution – Bill shape converges with mainland species utilizing similar resources (hummingbirds, grossbeaks)

Hawaiian Drepanids--Deadly Isolation • Extinction and Endangerment due to lack of resistance to exotics – humans, mosquitoes, rodents

• Trophic Cascade Effects – loss of pollinators leads to plant endangerment

Important Early Players

John J. Audubon (1785-1851)

Alexander Wilson (1766-1813)

John Townsend

John Burroughs, John Muir, Teddy Roosevelt and George Bird Grinnell

Was a naturalist with Custer, worked with TR to start Audubon

Set conservation policy and reserved important lands, especially in the west

Heightened awareness of Eastern and Western nature

Ornithological Societies of North America

A.O.U.

W.O.S.

C.O.S.

A.F.O.

Typical avian features 1. feathers 2. unique skull single occipital condyle cranial kinesis bills without teeth (in modern birds) gizzard (grinding or storage-crop) 3. hollow bones, many fusions 4. eggs 5. chambered heart 6. homeothermic, rapid BMR 7. lungs and air sacs 8. highly developed brain and nervous system

Unique Skeleton

4-chambered heart

• Homethermic,rapid BMR

• Lungs and air sacs

• Highly developed brain and nervous system

Early Evolution and Radiation of Birds • Mesozoic era—age of reptiles • Birds evolved from reptiles – Archaeopteryx 150 my in Jurasic

Birds Diverged from Reptiles after Mammals

From Tony Angell

But From Which Reptiles? • All agree birds came from Archosaurs (Archosauria is a crown group, consisting of birds, crocodiles, and all descendants of their most

• • • • •

recent common ancestor), but Crocodylia (crocs and gators) Saurischia (reptile hip dinos) Ornithischia (bird hip dinos) Pterosauria (flying reptiles) Thecodontia (ancestral group)

which group?

Hypotheses abound as to whether birds evolved from basal thecodonts, saurischians (the most common view), or crocodylia

The Prevalent View • Dinosaurs are icons of prehistory, and remain an important part of • the modern world in the form of some 10,000 living species of birds. Feathers, eggs, and parental care are known among the dinosaurs

Dinosaurs are icons of prehistory, and remain an important part of the modern world in the form of some 10,000 living species of birds. (Brusatte et al. 2010. Earth-Science Reviews 101:68-100)

Recent Evaluation of Alternative Hypotheses (James and Pourtless (2009, Ornithological Monographs No. 66)

Closest Relatives of Archaeopteryx and other birds are are maniraptoran, theropod dinosaurs (idea known as BMT hypothesis)

Archaeopteryx as Oldest Bird

(Chiappe and Dyke 2002)

Archaeopteryx v. Velocoraptor

Greg Erickson, Florida State University

(Chiappe and Dyke 2002)

A New Fossil Godefroit et al. 2013 Small Feathered Dinosaur, Basal Bird, The Avialae Clade

A New Phylogeny

A New Phylogeny

Hypotheses Are Still Being Tested

Greg Erickson, Florida State University

So, What is a Bird? • The Class Aves is “a node-based clade that includes Archaeopteryx, modern birds, their most recent common ancestor, and all its descendents” (James and Pourtless 2009) • Birds—as so defined--share only 3 derived morphological attributes (Chiappe 2002) – Caudal margin of the external naris nearly reaches or overlaps the rostral border of the antorbital cavity – A prominent acromion in the scapula – A pointy and shallow postacetabular wing of the ilium that has less that 50% the dorsovetral depth of the preacetabular wing at the acetabulum

• The Clade Avialae, which is a sister group of Dromaeosaurids • If it has a flight wing and avian feathers it’s a bird (Feduccia 2013)

Our Insights are Products of the Analysis • THE list of shared, derived characteristics held by all and only birds are questioned by some and reflect the author’s scoring schemes and pool of animals that are compared. Other analyses by other people provide some differences. As more fossils are discovered, scored, and analyzed the features of birds and the search for their closest relatives will become clearer.

Birding would have been dangerous

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