today
8:30 a.m. Audubon Society Field Trip See Event Description
read >8:30 a.m. Alzheimer’s Resource Center Volunteer Training See Event Description
read >9 a.m. Arcata Farmers' Market Arcata Plaza
read >9 a.m. Speakers' Symposium College of the Redwoods
read >9 a.m. Humboldt Botanical Gardens Foundation Speakers’ Symposium College of the Redwoods
read >9 a.m. Humboldt Botanical Gardens' Speakers' Symposium College of the Redwoods
read >9 a.m. Fall Rummage Sale Arcata United Methodist Church
read >9:30 a.m. AAUW Meeting See Event Description
read >9:30 a.m. Little River State Beach Restoration See Event Description
read >9:30 a.m. Sierra Club Headwaters Hike See Event Description
read >10 a.m. Lanphere Dunes Guided Walk See Event Description
read >10 a.m. 5th Annual Synergy Fair Arcata Community Center
read >10 a.m. Go Green and Boost Your Bottom Line Wharfinger Building
read >11 a.m. Sustaining Excellence and Enthusiasm in Health, Relationships and Work Carlo Theater (Dell'Arte)
read >noon KEET's Kids Club Morris Graves Museum of Art
read >1:30 p.m. Humboldt County Historical Society Humboldt County Library
read >2 p.m. Arcata Marsh Field Trip Arcata Marsh and Wildlife Sanctuary Interpretive Center
read >4 p.m. Woodside Preschool’s 36th Wine and Ale Tasting Gala Adorni Recreation Center
read >4:30 p.m. Harvest Dinner and Bazaar Humboldt Grange
read >5 p.m. A Toast to Music Christ Episcopal Church
read >5:30 p.m. Elvis and the Hound Dogs + Stolen Taxi Trinidad Town Hall
read >6 p.m. The Tumbleweeds Chapala Cafe
read >6 p.m. Arts Alive! Various Locations
read >6 p.m. Day of the Dead Exhibition Ink People Center for the Arts
read >6 p.m. Bar None 10th Anniversary Eureka Labor Temple
read >6 p.m. Randy Spicer Piante Gallery
read >6 p.m. Gallery Open for Arts Alive! Four Paths Gallery and Studio
read >6:30 p.m. ShinBone (Blues R&B) Eureka Theater
read >7 p.m. Mike Craighead and Sari Baker Old Town Coffee & Chocolates
read >7 p.m. Harvest Concert Arcata Presbyterian Church
read >7 p.m. 2 Left Feet Dance Project Redwood Raks World Dance Studio
read >7:30 p.m. Joe & Me Cafe Mokka
read >7:30 p.m. Cyrano de Begerac Eureka High School Auditorium
read >7:30 p.m. Torch Song Summit Eureka Women's Club
read >7:30 p.m. Jeff DeMark and the LaPatinas Westhaven Center for the Arts
read >8 p.m. Stones in His Pockets Arcata Playhouse
read >8 p.m. Humboldt Bay Brass Band Fulkerson Recital Hall at HSU
read >9 p.m. Synergy Six Rivers Brewery
read >9 p.m. Arts Alive! with Akaboom Sound Pearl Lounge
read >9 p.m. Tempest WAVE @ blue lake casino
read >9 p.m. Back In The Daze Dance Party Central Station Cocktail Lounge
read >9 p.m. Swingin' Country Band (country) Bear River Casino
read >9 p.m. The Zygoats + Alder Camp (rock) The Lil' Red Lion
read >9 p.m. DJ Knutz (funk) Muddy's Hot Cup
read >10 p.m. Music by DJ Sidelines
read >10 p.m. DJ Icy Hot Aunty Mo's Lounge
read >10 p.m. These United States (indie folk) Humboldt Brews
read >11 p.m. Hellbound Glory The Alibi Lounge and Restaurant
read >previous columns
July 17, 2008
Si, PV and LED
Silicon, PhotoVoltaics and Light Emitting Diodes are of growing importance. ...
read >July 10, 2008
Pupal Memories
I remember watching a chick emerge from an egg. It ...
read >July 3, 2008
Lagoons and Beaches
Lagoons Shelter Cove Much of our coastal topography is generated ...
read >Photos
Arms Race & Species
By Don Garlick
Herpetology, the study of amphibians and reptiles, sheds much light on the nature of evolution. Consider the range of body plans and lifestyles among salamanders (amphibians with tails). They commonly hatch from eggs in water or moist places, though a few species give birth to live young. Some are confined to water and use external gills. Some metamorphose into land crawlers and breathe with lungs. Surprisingly, most require neither gills nor lungs, but exchange gases through moist skin and mouth membranes. A local lungless species has such small legs that it resembles a tiny snake. The nine-inch Pacific Giant Salamander devours banana slugs. A Japanese salamander is almost six feet long.
Salamanders with drier skin are called newts. The Rough-skinned Newt (photo), ranging from Santa Cruz to Alaska, has a particularly toxic skin. If ingested, it can paralyze and kill several humans. That "tetrodotoxin" also occurs in Pufferfish and Blue-ringed Octopuses. In those marine animals, at least, the toxin is produced by symbiotic bacteria.
Garter Snakes have evolved an immunity to tetrodotoxin. It is clear that predation has driven newts to become increasingly toxic, and snakes to become increasingly immune. It's an example of co-evolution and a natural arms race. Moreover, after eating a newt, toxin resides in a snake's liver for weeks, undoubtedly affording it some protection from birds. On Vancouver Island, newts and snakes have avoided the chemical arms race. Canada is just more peace-loving.
An insight into speciation is provided by lungless Ensatina Salamanders, whose young, hatched from eggs under damp wood, resemble tiny adults. Several sub-species range southward on both sides of the Central Valley (map). Neighboring sub-species readily interbreed and blend, except those at the southern extreme of the range. These remain distinct because their hybrids have reduced vigor. Biologists consider the southern-end members to represent two different species.
Another example of a "ring species," demonstrating the gradual origin of species by increasing geographic separation, is provided by sea gulls: Gradual changes through 360 degrees around the Arctic Ocean culminate in two distinct species in northern Europe.
Be kind to salamanders -- our ancestors resembled them just 360 million years ago.
I thank Prof. Sharyn Marks of H.S.U. for correcting my errors.




















1. Don Garlick:
Aug. 20, 6:51 p.m.
The map caption is wrong (added by webmaster). Ensatina Salamanders are not Rough-skinned Newts.
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