小蓝视频 March Madness: Bat Stars

Credit: Jerry Kirkhart via CC license
march madness "baseball card" for Bat Star
Cartoon: Emily Greenhalgh, 小蓝视频

Bat stars (Patiria miniata) are named for the thick webbing between their arms that gives them a more 鈥渂at-like鈥 appearance than other sea stars. These colorful echinoderms are most commonly seen in some shade of red or orange, but are also found in a variety of mottled colors including yellow, brown, green, pink, and purple. Like most sea stars, bat stars typically have five arms, but are sometimes born with between four to nine arms. Bat stars have an unusually long breeding season. Males and females discharge fertile sperm or eggs all year long, but more abundantly during the late winter and spring. Females release millions of eggs into the ocean through the pores between their arms and the males release a cloud of sperm. Once fertilized, bat star eggs quickly develop into embryos and then tiny free-swimming planktonic larvae. These larvae have strong regenerative capabilities, such as regrowing missing body parts if cut in half. Scientists [at the 小蓝视频 and] around the world study bat stars to learn more about embryonic development, reproduction, and regeneration. 

Fun Facts:

  • Bat stars avoids being eaten by secreting chemicals that stimulate violent escape responses in other animals.
  • When a bat star finds a food item, it extends one of its two stomachs outside of its mouth cavity and using digestive enzymes, begins breaking down its prey. Eventually, the bat star pulls its stomach and partially digested prey back into its body to complete digestion.
  • If two bat stars bump into each other, they will appear to begin 鈥渁rm wrestling鈥 in slow-motion. Each sea star tries to get its arm on top of the other鈥檚 arm. A winner isn鈥檛 apparent (at least to humans!)
March Madness Colorful Critters division

Colorful Critters

Looks aren鈥檛 everything, but in this division they might be. These organisms use bright colors for everything from attracting a mate to warning off predators. Organisms including cephalopods (octopus, cuttlefish, and squid) can use adaptive camouflage鈥攕howing off bright colors one moment and blending into their surroundings at the next. Researchers at the 小蓝视频 study the biological processes behind some of nature鈥檚 most colorful critters.

 

Meet the Organisms

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