Conclusions - 2
The majority of amphibians have rapid reproductive rates, laying large numbers of eggs with little or no parental care (there are of course exceptions such as Darwin's frog, midwife toads, Pipa toads and others) these are essentially ôr" selected species. It would appear that Typhlonectes natans represents the opposite extreme: a ôKö selected species, characterized by a long life span, late maturity, and a very low rate of reproduction with extensive parental care (in this case a pregnancy lasting approximately 11 months). This is more commonly associated with animals like whales and elephants. For an amphibian this extreme example of ôkö selection is exceptional. In general ôKö selected species require stable habitats with constant environmental conditions in order to thrive. They are very vulnerable to sudden environmental changes and recover very slowly, if at all, from population declines.
A further complication is that the long life spans and low reproductive rates of such organisms make it very difficult to detect long-term breeding failures which may lead to population crashes. Concerns have been expressed because of large-scale global declines in amphibian populations. This led to the establishment of the Declining Amphibian Population Task Force (DAPTF) by the IUCN in order to monitor amphibian populations, and to use such declines as an environmental and ecological barometer. The unusual life history of Typhlonectes species makes them even more vulnerable to environmental change than the majority of amphibians and, although current populations do not appear to be undergoing significant declines, this should be carefully monitored.


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