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1 RT = 1 crab fact
For every retweet this tweet gets, I'll add one crab fact under the thread. Offer valid until the end of #CrabMonth.
(I feel like I'm gonna regret this stunt)
For every retweet this tweet gets, I'll add one crab fact under the thread. Offer valid until the end of #CrabMonth.
(I feel like I'm gonna regret this stunt)
1. Crabs are cute and pure don't @ me
2. There are more crabs species than all mammals combined, and this is just counting true crabs, not false crabs
3. The number of known true & false crabs species combined matches that of the birds at 10k, with many more yet to be discovered
2. There are more crabs species than all mammals combined, and this is just counting true crabs, not false crabs
3. The number of known true & false crabs species combined matches that of the birds at 10k, with many more yet to be discovered
4. Yes there are true crabs (Brachyura) & false crabs (Anomura)
5. Fiddler crabs, Japanese spider crab, most you know are true crabs
6. Hermit crabs, king crabs, mole crabs are false crabs
7. They're still crabs & cute this is 100% science
8. Horseshoe crab isn't even crustacean
5. Fiddler crabs, Japanese spider crab, most you know are true crabs
6. Hermit crabs, king crabs, mole crabs are false crabs
7. They're still crabs & cute this is 100% science
8. Horseshoe crab isn't even crustacean
9. True crabs mostly* have 4 pairs of visible legs
10. False crabs mostly* have 3 pairs of visible legs
11. True crabs mostly* have 2 pairs of short antennae
12. False crabs mostly* have 2 pairs of antennae: 1 short 1 long
13. *Crabs really like exceptions https://twitter.com/franzanth/status/1377953148728307717
10. False crabs mostly* have 3 pairs of visible legs
11. True crabs mostly* have 2 pairs of short antennae
12. False crabs mostly* have 2 pairs of antennae: 1 short 1 long
13. *Crabs really like exceptions https://twitter.com/franzanth/status/1377953148728307717
14. Together, they're all called meiurans
16. The group Meiura split into Brachyura (true) and Anomura (false) ~320 mil years ago
17. That's like 70 mil years before dinosaurs existed
18. The earliest meiurans likely looked like squat lobsters, not "proper" crabs
16. The group Meiura split into Brachyura (true) and Anomura (false) ~320 mil years ago
17. That's like 70 mil years before dinosaurs existed
18. The earliest meiurans likely looked like squat lobsters, not "proper" crabs
19. Those lobstery boys evolved the highly coveted crab body form at least 5 different times, independent from each other
20. This is called carcinization if you're into crab memes
21. This is why some crabs still look lobstery, not everyone got carcinized equally
20. This is called carcinization if you're into crab memes
21. This is why some crabs still look lobstery, not everyone got carcinized equally
22. Carcinization checklist: butt folded under the body, shell wider to the side than front/back, has a "chest shield" under the body (take note for your inevitable carcinization)
23. Crabs have since decarcinized at least 7 times
Disclaimer: hard science provided by @jopabinia
23. Crabs have since decarcinized at least 7 times
Disclaimer: hard science provided by @jopabinia
24. The oldest true crab fossil known today is Eoprosopon klugi
25. It was found near Erlangen, Germany
26. It's about 190 mil years old
27. That's older than Stegosaurus
28. It's smol, less than 4cm wide
29. Only one Eoprosopon has been found so far, it's lonely send help :(
25. It was found near Erlangen, Germany
26. It's about 190 mil years old
27. That's older than Stegosaurus
28. It's smol, less than 4cm wide
29. Only one Eoprosopon has been found so far, it's lonely send help :(
30. The oldest false crab fossil known today is Platykotta akaina
31. It was found in the United Arab Emirates
32. It's over 200 mil years old
33. It's slightly bigger, around 10cm long
34. It's somewhat lobstery, showing the non-carcinized body some crabs have (p.s. still cute)
31. It was found in the United Arab Emirates
32. It's over 200 mil years old
33. It's slightly bigger, around 10cm long
34. It's somewhat lobstery, showing the non-carcinized body some crabs have (p.s. still cute)
Hot damn that's a lot of RTs, you crab nerds.
I'll need to take a break and plan the tweets to make sure they don't feel jumpy/all over the place. I'll be back! At some point! I promise!
I'll need to take a break and plan the tweets to make sure they don't feel jumpy/all over the place. I'll be back! At some point! I promise!
How did you come up with 200 extra RTs when I was sleeping :|
Anyway enough fossil crabs for now, we'll cover more about it in #InsertAnInvert next week. I'll try to cover body parts now.
Anyway enough fossil crabs for now, we'll cover more about it in #InsertAnInvert next week. I'll try to cover body parts now.
35. Crabs have claws (lol)
36. The claws are basically legs, modified for grabbing
37. The arm has the same amount of segments as legs
38. Many crabs have "handedness"
39. If dominant claw is lost, some switch handedness
40. Oh yeah lost limbs grow back https://twitter.com/franzanth/status/1380523455464960000
36. The claws are basically legs, modified for grabbing
37. The arm has the same amount of segments as legs
38. Many crabs have "handedness"
39. If dominant claw is lost, some switch handedness
40. Oh yeah lost limbs grow back https://twitter.com/franzanth/status/1380523455464960000
41. Some fishermen harvest crab claws, not whole crabs
42. Arms are snapped clean on the joint to reduce infection
43. Do they feel pain? Unclear, but they respond to electric shock
44. Limbs regrow when they molt
45. That is, if they survive living with one arm, which many do
42. Arms are snapped clean on the joint to reduce infection
43. Do they feel pain? Unclear, but they respond to electric shock
44. Limbs regrow when they molt
45. That is, if they survive living with one arm, which many do
46. Shame-faced crabs, calappids, are round crabs with big claws covering the face
47. They're mostly right-handed
48. They live in shallow seas on sand
49. They eat snails, which are mostly "coiled to the right"
50. It's easier to peel right coiled snails if you're right-handed
47. They're mostly right-handed
48. They live in shallow seas on sand
49. They eat snails, which are mostly "coiled to the right"
50. It's easier to peel right coiled snails if you're right-handed
51. @Werner_deGier, my token calappid expert, thinks left-handed calappids exist
52. Again, basically they switch handedness when they lose an arm, survive, then molt
53. But there are more right-coiled snails than left-coiled snails so eating might be harder for lefty calappid
52. Again, basically they switch handedness when they lose an arm, survive, then molt
53. But there are more right-coiled snails than left-coiled snails so eating might be harder for lefty calappid
54. Handedness usually means the crab is doing something specific with 1 hand, other tasks with the other
55. That's why most "handed" crabs are predator
56. It's called Heterochely
57. Hetero = different, chela = claw
58. Crabs that filter feed/eat junk don't need 1 special claw
55. That's why most "handed" crabs are predator
56. It's called Heterochely
57. Hetero = different, chela = claw
58. Crabs that filter feed/eat junk don't need 1 special claw
59. Fiddler crabs have one massive claw, the other is tiny
60. Only the male is heterochelous
61. Females have 2 small claws and they're drab
62. They're not predators, they inhale junk and sand, like me
63. The big claw is for show only, not for eating https://www.inaturalist.org/observations/71266536
60. Only the male is heterochelous
61. Females have 2 small claws and they're drab
62. They're not predators, they inhale junk and sand, like me
63. The big claw is for show only, not for eating https://www.inaturalist.org/observations/71266536
64. They wave their arms to "talk" to each other
65. They change the way they wave depending on the audience
66. Here's a male doing a circular wave for a female http://www.momo-p.com/showdetail-e.php?movieid=momo091127ul01a
67. Here's a male doing a flick for another male http://www.momo-p.com/showdetail-e.php?movieid=momo091127ul02a
65. They change the way they wave depending on the audience
66. Here's a male doing a circular wave for a female http://www.momo-p.com/showdetail-e.php?movieid=momo091127ul01a
67. Here's a male doing a flick for another male http://www.momo-p.com/showdetail-e.php?movieid=momo091127ul02a
68. Here's a male doing a vertical wave for another male http://www.momo-p.com/showdetail-e.php?movieid=momo091127ul03a
69. Here's a male doing a circular wave... while eating http://www.momo-p.com/showdetail-e.php?movieid=momo091127ul04a
70. Anyway according to @JaviPaleobio, fiddlers don't change handedness when they lose their big claw
69. Here's a male doing a circular wave... while eating http://www.momo-p.com/showdetail-e.php?movieid=momo091127ul04a
70. Anyway according to @JaviPaleobio, fiddlers don't change handedness when they lose their big claw
71. You could kinda guess what a crab eats based on the claw shape
72. But not really, crabs like exceptions
73. They're mostly opportunistic omnivores that eat whatever's free and available from algae to carcass
74. But big claws are more likely to be used for crushing shellfish
72. But not really, crabs like exceptions
73. They're mostly opportunistic omnivores that eat whatever's free and available from algae to carcass
74. But big claws are more likely to be used for crushing shellfish
75. Graceful kelp crabs, for example, mostly eat kelp (duh)
76. They live in the kelp forests of Pacific coast North America
77. Very smol and cute
78. Their claws are small and slender
79. Definitely more useful for grazing, not crushing shells https://www.inaturalist.org/observations/49409431
76. They live in the kelp forests of Pacific coast North America
77. Very smol and cute
78. Their claws are small and slender
79. Definitely more useful for grazing, not crushing shells https://www.inaturalist.org/observations/49409431
80. Other crabs use their slender claws for defense
81. They trim algae for fashion
82. Graceful decorator crab has velcro on its back to attach junk to
83. There are many species of decorators
84. It's hard to tell them apart because of all their junk https://www.inaturalist.org/observations/69293763
81. They trim algae for fashion
82. Graceful decorator crab has velcro on its back to attach junk to
83. There are many species of decorators
84. It's hard to tell them apart because of all their junk https://www.inaturalist.org/observations/69293763
85. I once found 4 dead decorators near one rock
86. 3 of them might be the same species
87. Their fashion choice is visibly personal
88. They covered themselves with different things
89. The amount of junk is also different, making them hard to identify https://twitter.com/franzanth/status/1123958290881437701
86. 3 of them might be the same species
87. Their fashion choice is visibly personal
88. They covered themselves with different things
89. The amount of junk is also different, making them hard to identify https://twitter.com/franzanth/status/1123958290881437701
90. The Hawaiian pom-pom crab carries pom-poms around to fight
91. They're stinging anemones
92. Anemones reproduce by splitting in half, so a crab missing one pom-pom has been observed holding its one anemone with both claws until it split in two https://www.inaturalist.org/observations/71093231
91. They're stinging anemones
92. Anemones reproduce by splitting in half, so a crab missing one pom-pom has been observed holding its one anemone with both claws until it split in two https://www.inaturalist.org/observations/71093231
93. Not all crabs carry things on their back/with their claws
94. Crabs that carry with their legs evolved hooks on their last pair (or two) of legs
95. The hooks are specialized leg tips
96. The hook legs are smaller and raised up, unfit for walking https://www.inaturalist.org/observations/24370440
94. Crabs that carry with their legs evolved hooks on their last pair (or two) of legs
95. The hooks are specialized leg tips
96. The hook legs are smaller and raised up, unfit for walking https://www.inaturalist.org/observations/24370440
97. This is the leaf porter crab
98. Found in North Singapore
99. Tiny, only 1-2cm
100. During the day, it chills under a leaf
101. At night it swims UPSIDE DOWN carrying a leaf on its back
102. It swims at surface so hungry fishes below only see a leaf https://www.inaturalist.org/observations/19814477
98. Found in North Singapore
99. Tiny, only 1-2cm
100. During the day, it chills under a leaf
101. At night it swims UPSIDE DOWN carrying a leaf on its back
102. It swims at surface so hungry fishes below only see a leaf https://www.inaturalist.org/observations/19814477
103. Some crabs carry random junk, some picky
104. The urchin crab only carries sea urchins
105. In fact, it only carries long, hollow spined urchins because they're light & very ouch
106. The urchins can technically run away but seem ok with the free ride https://www.inaturalist.org/observations/20549015
104. The urchin crab only carries sea urchins
105. In fact, it only carries long, hollow spined urchins because they're light & very ouch
106. The urchins can technically run away but seem ok with the free ride https://www.inaturalist.org/observations/20549015
Change of plans:
- I just realized people can only RT once but QRT over and over
- The numbers are taking so much of my character limit, it's getting harder to make sure the tweets flow better
- Therefore, the hard cap is now 1000 crab facts
(that's still a lot of crab facts)
- I just realized people can only RT once but QRT over and over
- The numbers are taking so much of my character limit, it's getting harder to make sure the tweets flow better
- Therefore, the hard cap is now 1000 crab facts
(that's still a lot of crab facts)
107. This is a sponge crab
108. It wears hats made of sponge
109. It's for camouflage
110. The hat is personally trimmed with claws to fit the crab
111. The hat is alive
112. It grows alongside the crab
113. The crab clings onto the hat with its hook legs https://www.inaturalist.org/observations/11258187
108. It wears hats made of sponge
109. It's for camouflage
110. The hat is personally trimmed with claws to fit the crab
111. The hat is alive
112. It grows alongside the crab
113. The crab clings onto the hat with its hook legs https://www.inaturalist.org/observations/11258187
114. Its hat isn't always sponge
115. Another popular choice is colonial ascidians, which are also animals
116. Others have been seen wearing corals
117. Anemones
118. Algae
119. Sandal
120. Half a tennis ball
121. When they're older they ditch the hat :( https://www.nationalgeographic.com/animals/article/crabs-make-hats-using-sponges
115. Another popular choice is colonial ascidians, which are also animals
116. Others have been seen wearing corals
117. Anemones
118. Algae
119. Sandal
120. Half a tennis ball
121. When they're older they ditch the hat :( https://www.nationalgeographic.com/animals/article/crabs-make-hats-using-sponges
122. There are more fancy variants of crab legs
123. Many have paddle legs for swimming
124. Example: the blue crab, commonly eaten in eastern US
125. The Marylanders are so proud of their crab, I'm tweeting this because they kept asking for it https://www.inaturalist.org/observations/73671578
123. Many have paddle legs for swimming
124. Example: the blue crab, commonly eaten in eastern US
125. The Marylanders are so proud of their crab, I'm tweeting this because they kept asking for it https://www.inaturalist.org/observations/73671578
126. Many commercially important crabs are in the family Portunidae—swimming crabs
127. There are two genera eaten in SE Asia named Scylla & Charybdis
128. Named after the Greek myth
129. Hard to cultivate Scylla serrata because they keep eating each other https://www.inaturalist.org/observations/27850005
127. There are two genera eaten in SE Asia named Scylla & Charybdis
128. Named after the Greek myth
129. Hard to cultivate Scylla serrata because they keep eating each other https://www.inaturalist.org/observations/27850005
130. Flat paddle legs are also useful for digging
131. Moon crabs, family Matutidae, are really flat & round
132. They like to hide under the sand
133. Ashtoret is named after the Phoenician moon goddess Astoreth
134. I scooped up this goddess with a croc https://www.inaturalist.org/observations/31217711
131. Moon crabs, family Matutidae, are really flat & round
132. They like to hide under the sand
133. Ashtoret is named after the Phoenician moon goddess Astoreth
134. I scooped up this goddess with a croc https://www.inaturalist.org/observations/31217711
135. Spanner crabs, Raninidae, came equipped for digging
136. Their legs are basically spades
137. Even their claws are flat
138. They're also called frog crabs
139. Because they do sit like crabs
140. Even the scientific name refers to the word Rana, frog https://www.inaturalist.org/observations/28219401
136. Their legs are basically spades
137. Even their claws are flat
138. They're also called frog crabs
139. Because they do sit like crabs
140. Even the scientific name refers to the word Rana, frog https://www.inaturalist.org/observations/28219401
141. Crabs' walking legs are just as diverse
142. Some naked, some hairy
143. Some smooth, some spiky
144. Some long, some stubby
145. You already know that the largest crab, Japanese spider crab, is mostly legs
146. But umbrella crab legs? barely visible https://www.inaturalist.org/observations/24692444
142. Some naked, some hairy
143. Some smooth, some spiky
144. Some long, some stubby
145. You already know that the largest crab, Japanese spider crab, is mostly legs
146. But umbrella crab legs? barely visible https://www.inaturalist.org/observations/24692444
147. When seen from above? Absolutely ridiculous
148. It's mostly shell
149. They're scientifically called Cryptolithodes
150. It means cryptic stone, not wrong tbh
151. Geologists probably shouldn't lick this
152. It's a member of the king crab family https://www.inaturalist.org/observations/19845827
148. It's mostly shell
149. They're scientifically called Cryptolithodes
150. It means cryptic stone, not wrong tbh
151. Geologists probably shouldn't lick this
152. It's a member of the king crab family https://www.inaturalist.org/observations/19845827
153. This is also a whole real crab
154. It's Cryptolithodes sitchensis
155. Lives in the intertidal zone
156. Its natural range is Alaska-California
156. It's hard to see, easy to catch, because stubby legs
157. I just want to post this because it's cute https://www.inaturalist.org/observations/3702592
154. It's Cryptolithodes sitchensis
155. Lives in the intertidal zone
156. Its natural range is Alaska-California
156. It's hard to see, easy to catch, because stubby legs
157. I just want to post this because it's cute https://www.inaturalist.org/observations/3702592
I can't wait to tweet about not-crabs, but alas, I have (at least) 700 more facts to write before the month ends.
I'm taking a break, but tomorrow I'll tweet about crab butts.
I'm taking a break, but tomorrow I'll tweet about crab butts.
Today's crab butt & hermit crab facts are provided by @jopabinia
158. So crabs are arthropods
159. Arthropods have segmented bodies
160. The crab's "main body" is its cephalothorax
161. It's the equivalent to a shrimp's "head" https://www.inaturalist.org/observations/33413779
158. So crabs are arthropods
159. Arthropods have segmented bodies
160. The crab's "main body" is its cephalothorax
161. It's the equivalent to a shrimp's "head" https://www.inaturalist.org/observations/33413779
162. When we eat shrimps, the fleshy part is the abdomen/"butt"
163. In (many) crabs, butt is flat & folded under the cephalothorax
164. It's one of the features of carcinization
165. The butt is also called pleon
166. Poop comes out of the pleon's end https://www.inaturalist.org/observations/74375548
163. In (many) crabs, butt is flat & folded under the cephalothorax
164. It's one of the features of carcinization
165. The butt is also called pleon
166. Poop comes out of the pleon's end https://www.inaturalist.org/observations/74375548
167. You can sex many crabs by looking at their pleons 
168. Male pleons are narrow
169. Female pleons are wider
170. They're for carrying eggs
171. True crabs have knobs and sockets to lock the pleon shut
172. Like shrimp butt, there are tiny feet attached to crab pleons too
168. Male pleons are narrow
169. Female pleons are wider
170. They're for carrying eggs
171. True crabs have knobs and sockets to lock the pleon shut
172. Like shrimp butt, there are tiny feet attached to crab pleons too
173. At the end of a shrimp butt is the tail fan
174. They're technically "legs"
175. Called uropods
176. In crabs, the uropods are reduced
177. But not in hermit crabs
178. Their uropods are more leggy than fanny
179. And used for clinging to its home https://www.inaturalist.org/observations/73754206
174. They're technically "legs"
175. Called uropods
176. In crabs, the uropods are reduced
177. But not in hermit crabs
178. Their uropods are more leggy than fanny
179. And used for clinging to its home https://www.inaturalist.org/observations/73754206
180. Hermits famously live in snail shells
181. But they have also been seen living in tunicate
182. And sponge
183. Tubeworm
184. Tusk shell
185. Coral
186. And of course our trash
187. But hermits living in snail shells grow a coiled pleon to fit into it https://www.inaturalist.org/observations/24220104
181. But they have also been seen living in tunicate
182. And sponge
183. Tubeworm
184. Tusk shell
185. Coral
186. And of course our trash
187. But hermits living in snail shells grow a coiled pleon to fit into it https://www.inaturalist.org/observations/24220104
188. The hermit Sympagurus dofleini has a symbiosis with Stylobates anemones
189. The anemone gets free ride & food scraps
190. The crab gets a bodyguard
191. The crab originally lives in a snail shell
192. Anemone dissolves the shell, builds a new one https://twitter.com/squamiferum/status/715923298463297536
189. The anemone gets free ride & food scraps
190. The crab gets a bodyguard
191. The crab originally lives in a snail shell
192. Anemone dissolves the shell, builds a new one https://twitter.com/squamiferum/status/715923298463297536
