Home›Mammals›NatureServe RankBrowse ByNatureServe RankFactsNatureServe RankSourcesComments (0)Reader Challenges (0)FactsComparisonReproductive ModeWell-attestedViviparous (Live-Bearing) 1NatureServe RankG1 Critically ImperiledNatureServe Rank2 entriesG2 ImperiledNatureServe Rank2 entriesG3 VulnerableNatureServe Rank10 entriesG4 Apparently SecureNatureServe Rank30 entriesG5 SecureNatureServe Rank63 entriesGNA Not ApplicableNatureServe Rank4 entriesGNR UnrankedNatureServe Rank3 entriesGX Presumed ExtinctNatureServe Rank2 entriesSources1. Wikipedia: Mammaltier 2WikipediaMammal, lead sectionQuote, Mammal, lead sectionAll modern mammals give birth to live young, except the five species of monotremes, which lay eggs.View the SourceComments (0)No comments yet. Be the first to share a thought.Sign in to join the discussion.Reader Challenges (0)No disputes yet. Spotted an error or a better source? Open the first one.Sign in to dispute this or suggest a correction.