The three phases of the ensemble forecasting of niche models: geographic range and shifts in climatically suitable areas of Utetheisa ornatrix (Lepidoptera, Arctiidae)

Abstract

ABSTRACT. The three phases of the ensemble forecasting of niche models: geographic range and shifts in climatically suitable areas of Utetheisa ornatrix (Lepidoptera, Arctiidae). Species' geographic ranges are usually considered as basic units in macroecology and biogeography, yet it is still difficult to measure them accurately for many reasons. About 20 years ago, researchers started using local data on species' occurrences to estimate broad scale ranges, thereby establishing the niche modeling approach. However, there are still many problems in model evaluation and application, and one of the solutions is to find a consensus solution among models derived from different mathematical and statistical models for niche modeling, climatic projections and variable combination, all of which are sources of uncertainty during niche modeling. In this paper, we discuss this approach of ensemble forecasting and propose that it can be divided into three phases with increasing levels of complexity. Phase I is the simple combination of maps to achieve a consensual and hopefully conservative solution. In Phase II, differences among the maps used are described by multivariate analyses, and Phase III consists of the quantitative evaluation of the relative magnitude of uncertainties from different sources and their mapping. To illustrate these developments, we analyzed the occurrence data of the tiger moth, Utetheisa ornatrix (Lepidoptera, Arctiidae), a Neotropical moth species, and modeled its geographic range in current and future climates.KEYWORDS. Arctiidae; climate change; geographic range; niche models; uncertainty.RESUMO. As três fases da projeção combinada de modelos de nicho: distribuição geográfica e deslocamento de áreas climaticamente adequadas para Utetheisa ornatrix (Lepidoptera, Arctiidae). A distribuição geográfica das espécies tem sido considerada como a unidade básica em macroecologia e biogeografia, mas ainda há dificuldades em mensurá-la de forma adequada, por diferentes razões. Há cerca de 20 anos atrás, os pesquisadores começaram a utilizar dados locais da ocorrência das espécies para estimar essas distribuições utilizando modelos de nicho ecológico. Entretanto, ainda há uma série de problemas na avaliação dos modelos e em suas aplicações, e uma das soluções é utilizar um consenso de diferentes modelos, projeções climáticas, cenários de emissão e combinação de variáveis, que são fontes de incerteza durante o processo de modelagem de nicho. Neste artigo nós discutimos essa abordagem de consenso e a dividimos em três fases, com níveis crescentes de complexidade. A Fase I é simplesmente a combinação de mapas e a obtenção e interpretação de um único mapa de consenso. A Fase II envolve a descrição das diferenças entre os mapas utilizando técnicas de análise multidimensional, enquanto que a Fase III consiste em analisar quantitativamente e mapear a magnitude relativa das diferentes fontes de incerteza. A fim de ilustrar essa abordagem, nós analisamos dados de ocorrência de Utetheisa ornatrix (Lepidoptera, Arctiid...

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