''Linanthus parryae'' is a species of flowering plant in the
phlox family known by the common name sandblossoms. It is native to the western United States, growing in states including Oregon, Idaho, Wyoming, California, Nevada, Arizona, New Mexico, and Colorado. In California, it grows in several regions from the
Central Valley to the
Sierra Nevada foothills
:''See Sierra Nevada for general information about the mountain range in the United States.''
The ecology of the Sierra Nevada, located in the U.S. states of California and Nevada, is diverse and complex: the plants and animals are a significan ...
and the
Mojave Desert
The Mojave Desert ( ; mov, Hayikwiir Mat'aar; es, Desierto de Mojave) is a desert in the rain shadow of the Sierra Nevada mountains in the Southwestern United States. It is named for the indigenous Mojave people. It is located primarily ...
. It occurs in sandy, open, flat areas. This is a petite annual herb producing short stems just a few centimeters tall surrounded by hairy, needle-lobed leaves. The
inflorescence
An inflorescence is a group or cluster of flowers arranged on a Plant stem, stem that is composed of a main branch or a complicated arrangement of branches. Morphology (biology), Morphologically, it is the modified part of the shoot of sperma ...
, which often appears to sit directly on the ground tucked amidst the leaves, is a cluster of
funnel-shaped flowers about a centimeter wide. The flowers are self-incompatible and are cross-pollinated exclusively by
Melyrid beetle, ''Trichochorous'' sp.ref name="Schemske & Bierzychudek 2001">Schemske, D. W. & P. Bierzychudek. (2001)
Perspective: Evolution of flower color in the desert annual ''Linanthus parryae'': Wright revisited. ''Evolution'' 55:7 1269-82. Seeds germinate after winter rains in January to February, producing flowering plants in April and shedding seeds in May to June.
[Schemkse DW & Bierzychudek P (2007) Spatial differentiation for flower color in the desert annual ''Linanthus parryae'': was Wright right? Evolution 61-11: 2528-2543 DOI:10.1111/j.1558-5646.2007.00219.x] Seeds are passively dispersed and remain viable for at least seven years, with no germination in dry years.
The flowers on a plant may be white or blue. Flower color is mainly controlled by a single gene locus, with the allele for white flowers being recessive and the alleles of the blue flower being of the dominant type.
Most populations have predominantly white flowers, with some populations mainly blue flowers, and some others with both blue and white flowered plants occurring at intermediate frequencies.
The proportions of each color remain quite stable over time and in some locations there are sharp transitions from blue to white flowered populations.
This uncommon phenomenon has made this species a
model organism in studies of
genetic variation.
For many decades a long line of
geneticist
A geneticist is a biologist or physician who studies genetics, the science of genes, heredity, and variation of organisms. A geneticist can be employed as a scientist or a lecturer. Geneticists may perform general research on genetic processes ...
s and
botanists, including
Sewall Wright
Sewall Green Wright FRS(For) Honorary FRSE (December 21, 1889March 3, 1988) was an American geneticist known for his influential work on evolutionary theory and also for his work on path analysis. He was a founder of population genetics alongsi ...
,
Carl Epling
Carl Clawson Epling (15 April 1894 – 17 November 1968) was an American botanist and taxonomist. He is best known for being the major authority on the Lamiaceae (mint family) of the Americas from the 1920s to the 1960s. In his later years he als ...
,
Harlan Lewis
Frank Harlan Lewis (January 8, 1919 – December 12, 2008) was an American botanist, geneticist, taxonomist, systematist, and evolutionist who worked primarily with plants in the genus ''Clarkia''. He is best known for his theories of "catastro ...
and
T. G. Dobzhansky, have studied populations of this flower to determine the factors that influence this
polymorphism. Color frequencies may vary for many reasons, including
genetic drift
Genetic drift, also known as allelic drift or the Wright effect, is the change in the frequency of an existing gene variant (allele) in a population due to random chance.
Genetic drift may cause gene variants to disappear completely and there ...
and pure
natural selection
Natural selection is the differential survival and reproduction of individuals due to differences in phenotype. It is a key mechanism of evolution, the change in the heritable traits characteristic of a population over generations. Cha ...
. Wright built his
isolation by distance and
Shifting Balance theories on genetic drift in this flower using data collected by Epling and Dobzhansky in the Mojave Desert.
More recent studies place greater emphasis on the effects of natural selection on color frequency.
[Turelli, M., et al. (2001)]
Stable two-allele polymorphisms maintained by fluctuating fitnesses and seed banks: Protecting the blues in ''Linanthus parryae''.
''Evolution'' 55:7 1283-98.
References
External links
Jepson Manual TreatmentPhoto gallery
{{Taxonbar, from=Q6550260
parryae
Plant models
Endemic flora of California
Flora without expected TNC conservation status