CK,
I returned from my trip to S. Calif. about a week ago and now have time to address some of the comments contained in your April 19th post.

You quoted a passage from the 'Discussion' section in Javier's paper as follows: "...the Sierra Nevada and the Northwestern subclades...have completely allopatric distributions, with a break that occurs somewhere in the vicinity of Lassen Volcanic National Park in northeastern California (between the localities of C. b. bottae samples 6 and 14, which lie about 120 (airline) km apart; Fig. 1)."

It is normal for a reader of published research to automatically assume that the authors were factually correct in making statements. But in this case with the issue of allopatry, they clearly didn't. Let me first mention that Glenn Stewart sent me a draft of the mtDNA paper to review. I made a number of comments one of which questioned the claim of allopatry. At the time, Glenn explained why he thought Javier had indicated that to be the case and although I totally disagreed, I did not continue to challenge that point thinking that the editor or reviewers would pick up on that issue. In hindsight, the reviewers dropped the ball as well.

As a matter of fact, there are a number of flaws in that particular section of the paper. For instance, Table #1 indicates the origin of sample # 6 is from Eagle Lake, Lassen Co., #14 from Forest Road 17, Nevada Co., and #15 from Greenhorn Creek, Plumas Co. Due east of Mt. Lassen, Plumas and Lassen Counties adjoin. Nevada County is immediately
south of Plumas Co. Then when you view Fig. 1, you will note that the arrow has Nevada County sample #14 being situated above Plumas County sample #15 whereas it should be below sample #15.

In supposed support for claiming the two subclades have an allopatric distribution, the authors then site a distance of 120 direct kilometers between samples #6 and #14. The authors overlooked the fact that specimen #15 in Plumas county is closer to sample #6. And if my memory serves me correctly, when I checked a few years ago, sample #6 and #15 are about 60 km apart.

But I ask, how does the distance between vouchers provide support for allopatry? I have no idea of how the authors arrived at the notion that citing a distance between where two voucher specimens originate is support for allopatry. It would seem to me they didn't think through that situation very well nor did the reviewers do their job by challenging that point. If one understands the (mostly) random nature of how specimens become voucher, citing distances as support for any particular conclusion about a species is quite risky.

So the major error made is the statement you quote is the authors stating the two subclades are allopatric in distribution. Again, with not having spoken to Javier in that connection, I haven't any idea where such a notion arose. You might note that they do not cite any reference in support of their claim nor is there any reference to personal observations by any of the authors. New information stated as if factual in research publications should automatically be suspect when such claims lack support or verification of any sort.

At the time of the publication, many years had passed since I had been in the vicinity of Mt. Lassen. So during subsequent trips south to S. Calif. or on the return trips, I made it a point to travel all around that region and even took time to make some searches. As had been my impression from bygone years, suitable Rubber Boa habitat is extensive in all directions and unbroken throughout and beyond the immediate Mt. Lassen region.

During my trips, I collected two specimens in eastern Shasta Co near Burney approximately 25 - 30 miles slightly northwest of Mt. Lassen. Another specimen was collected in western Lassen County just east of the Shasta Co. line and about 15 miles slightly northeast of Mt. Lassen. Two other specimens were found in extreme northeastern Tehama County slightly southeast of Mt. Lassen by about 15 miles and just 2 - 3 miles from Plumas County. A few years ago, Chris Feldman and another grad student at Utah State U. collected a number of specimens for CAS near Mt. Lassen either in Lassen and / or adjacent Plumas counties, reasonably close proximity to Mt. Lassen, and in-between localities represented by specimens #6 and #15. Coupled with the knowledge of extensive and unbroken suitable boa habitat in that region, these recent findings dispel any notion of allopatry existing between the two subclades. That members of the two subclades interbreed is highly probable.

Accepting the author's claim of allopatry, you mentioned the remote possibility that the members of the two subclade would be reproductively incompatible. In my efforts to possibly shed light on the inheritance of the size factor(s), I have made the following crosses between males of the Sierra Nevada subclade and females of the Northwestern subclade.

dwarf morph Tehachapi Mt., Kern Co. male X large morph, Blodgett. Benton Co., Oregon female
dwarf morph Tehachapi Mt., Kern Co. male X large morph Mendocino County, Calif. female
dwarf morph Tehachapi Mt., Kern Co. male X large morph Starker Pit, Benton Co., Oregon female

Below are the reciprocal crosses made between males of the Northwestern subclade and females of the Sierra Nevada subclade.

large morph Berkeley, Alameda Co., Calif. male X dwarf morph female, Breckenridge Mt., Kern Co., Calif.
large morph Berkeley, Alameda Co., Calif. male X dwarf morph female, Poso Creek , Kern Co., Calif.
large morph Chapman site, Benton Co., Oregon male X dwarf morph female, Breckenridge Mt., Kern Co., Calif.

For the most part, the above crosses resulted in full term, live neonates with a few stillbirths.

With my understanding that distribution of the species is continuous from Kern Co. to British Columbia and the likelihood that the subclades are interbreeding, I have not undertaken crosses between large morphs of the two subclades.

When I was operating under the permits held by Dr. Stewart, my initial cross in 1996 was between a Northern Clade large morph female from Oregon and a Southern Clade dwarf male from the San Bernardino Mts. That cross produced 4 full term, live neonates, two male and two females. One of the female neonates died for unknown reasons and during the second or third year, one of the males died after eating a juvenile Ensatina.

The one surviving F-1 female proved to be fertile as a few years ago, she was backcrossed to a dwarf morph male and produced a litter. The fact that a cross between the two major clades produced fertile offspring lends credence to the notion that crosses between the two subclades should also produce fertile offspring. But since it takes from 6 - 10 years before female specimens reach sexual maturity, there hasn't been enough time for any of those F-1 specimens to have reached maturity at this point.

And just to add some added information to ponder, crosses between dwarf morph males and large morph female have produced only large morph neonates. Crosses between dwarf morph females and large morph males have produced only dwarf morph neonates.

Richard F. Hoyer

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