Complex sentence: Toxicity of individual specimens within the same species and subspecies can vary greatly based on several factors including geographical region and even the weather and altitude can influence toxicity (Ernst and Zug et al.1996).
Split into simpler sentences: Toxicity of individual specimens within the same species and subspecies can vary greatly based on several factors, including geographical region. Even the weather and altitude can influence toxicity (Ernst and Zug et al.1996).