---
_id: '3670'
abstract:
- lang: eng
text: The grasshopper Podisma pedestris includes two chromosomal races, which differ
by a Robertsonian fusion involving the sex chromosome. The two races meet in a
cline which runs for 100 km across the Alpes Maritimes in south-eastern France.
An intensive study of the easternmost end of this cline shows that it is about
800 m wide; the cline is not smooth, containing substantial spikes in chromosome
frequency which might be due to sampling drift. Though the cline seems narrow,
it is wide compared with the dispersal rate of the insect; a selective force of
only 0.5% would be enough to maintain the cline. It is difficult to determine
the nature of this force, but some evidence comes from the position of the cline,
and from the presence of coincident clines at other loci. An estimate of the distribution
of Podisma has been made, and the cline seems to follow, for the most part, a
region of low population density, suggesting that it is maintained by hybrid unfitness.
However, in the one region where the cline is relatively free to move, the XY
race bulges forwards more than would be expected if hybrids are unfit. The observation
of severe inviability in crosses between the races, though it is not associated
with the chromosomal difference, also indicates that this cline is the result
of some sort of genetic incompatibility.
acknowledgement: "Many thanks are due to the Hewitt family (Elizabeth, Daniel, Matthew,
and James), Bruce and Helen Halliday, Mike\r\n Shaw, Alan Jenyon, and Bob Williams
for their help in collecting the grasshoppers; to M. and Mme. Aviotti for their
hospitality in Casterino; and to Marise East for her help in karyotyping the samples.
The work was supported by a grant from the S.R.C. to G. Hewitt, and N. Barton was
supported by a N.E.R.C. studentship."
article_processing_charge: No
article_type: original
author:
- first_name: Nicholas H
full_name: Barton, Nicholas H
id: 4880FE40-F248-11E8-B48F-1D18A9856A87
last_name: Barton
orcid: 0000-0002-8548-5240
- first_name: Godfrey
full_name: Hewitt, Godfrey
last_name: Hewitt
citation:
ama: Barton NH, Hewitt G. A chromosomal cline in the grasshopper Podisma pedestris.
Evolution; International Journal of Organic Evolution. 1981;35(5):1008-1018.
doi: 10.1111/j.1558-5646.1981.tb04966.x
apa: Barton, N. H., & Hewitt, G. (1981). A chromosomal cline in the grasshopper
Podisma pedestris. Evolution; International Journal of Organic Evolution.
Wiley-Blackwell. https://doi.org/
10.1111/j.1558-5646.1981.tb04966.x
chicago: Barton, Nicholas H, and Godfrey Hewitt. “A Chromosomal Cline in the Grasshopper
Podisma Pedestris.” Evolution; International Journal of Organic Evolution.
Wiley-Blackwell, 1981. https://doi.org/
10.1111/j.1558-5646.1981.tb04966.x.
ieee: N. H. Barton and G. Hewitt, “A chromosomal cline in the grasshopper Podisma
pedestris,” Evolution; International Journal of Organic Evolution, vol.
35, no. 5. Wiley-Blackwell, pp. 1008–1018, 1981.
ista: Barton NH, Hewitt G. 1981. A chromosomal cline in the grasshopper Podisma
pedestris. Evolution; International Journal of Organic Evolution. 35(5), 1008–1018.
mla: Barton, Nicholas H., and Godfrey Hewitt. “A Chromosomal Cline in the Grasshopper
Podisma Pedestris.” Evolution; International Journal of Organic Evolution,
vol. 35, no. 5, Wiley-Blackwell, 1981, pp. 1008–18, doi: 10.1111/j.1558-5646.1981.tb04966.x.
short: N.H. Barton, G. Hewitt, Evolution; International Journal of Organic Evolution
35 (1981) 1008–1018.
date_created: 2018-12-11T12:04:32Z
date_published: 1981-09-01T00:00:00Z
date_updated: 2022-01-21T08:51:51Z
day: '01'
doi: ' 10.1111/j.1558-5646.1981.tb04966.x'
extern: '1'
external_id:
pmid:
- '28581059'
intvolume: ' 35'
issue: '5'
language:
- iso: eng
main_file_link:
- url: http://www.jstor.org/stable/2407871
month: '09'
oa_version: None
page: 1008 - 1018
pmid: 1
publication: Evolution; International Journal of Organic Evolution
publication_identifier:
eissn:
- 1558-5646
issn:
- 0014-3820
publication_status: published
publisher: Wiley-Blackwell
publist_id: '2713'
quality_controlled: '1'
status: public
title: A chromosomal cline in the grasshopper Podisma pedestris
type: journal_article
user_id: ea97e931-d5af-11eb-85d4-e6957dddbf17
volume: 35
year: '1981'
...