Anachronism on illusion of density-independence in biology

Date: Mon, 20 Jun 2016 16:49:41 +0900
A leader of Japanese fisheries scientist, Kazumi Sakuramoto, wrote an article "Illusion of a density-dependent effect in biology"

I was much surprised that this article was accepted by a journal "Agricultural Sciences".

I have the following comments:
1. It is well known that a simple statistical test of correlation makes an artifact of density dependence (Dennis & Taper 1994).
2. But there is a rigorous method to detect density dependence (Dennis & Taper 1994). Not a few real time series showed statistically significant density dependence, although we cannot detect density dependence from some poor time series.
3. (Lack of density-dependence) have now been rejected on logical grounds, and it is generally accepted that　population regulation cannot occur in the absence of density dependence (Turchin 1995).
4. Definitely density-dependence and environmental fluctuation are not mutually exclusive. It has been well known in international fisheries management organizations.
5. MSY [Maximum sustainable yield] theory is definitely based on density-dependence, but it does not mean that MSY theory must be adopted if density dependence really exists.

References
Sakuramoto K (2015) Illusion of a Density-Dependent Effect in Biology. Agricultural Sciences, 6: 479-488
Turchin P (1995) Population regulation: old arguments and a new synthesis. N. Cappuccino, P.W. Price (Eds.), Population Dynamics, Academic Press (1995), pp. 19–40

Dennis B, Taper ML (1994) Density dependence in time series observations of natural populations: Estimation and testing. Ecol Monogr 64:205-224.

Illusion of a Density-Dependent Effect in Biology? Incredible back to a 1950s controversy.
http://dx.doi.org/10.4236/as.2015.65047

Population changes are believed to be controlled by multiple factors, including an important density-dependent effect. This paper reviews the literature on this topic and shows that this density-dependent effect does not exist. This paper also gives a typical example in which no density-dependent effect was detected in the stock-recruitment relationship in Japanese sardines. The recruitment was found to be determined in proportion to the spawning stock biomass and to be affected by environmental factors. This simple mechanism is applicable not only in fish species but also in insects such as Thrips imaginis in Australia. The reason that many biologists have not become aware that the density-dependent effect does not exist is discussed using a metaphor. This paper proposes a new concept in the study of population change. The new concept proposed here will replace the currently used basic concept that has been assumed to be correct for more than 50 years.