By far, the most successful group of animals on our planet are the invertebrates. In terms of both sheer numbers and biomass we animals with spines just cannot compare. The current edition of the carnival that celebrates these spineless creatures just happens to be hosted by one of my favourite bird bloggers, John over at A DC Birding Blog. John usually blogs about birds, his birding forays and keeps the rest of us informed about birds in the news. His blog is always worth a stop. And the Circus of the Spineless #30? How can you resist posts about slug sex, or venomous spiders or creatures that take over other animals reproduction systems?