Table 2 Divergence times for the major groups of arthropods. Divergence times from least squares (LS) methods are means (<30 proteins) or modes of time estimates from individual proteins. Summary times are averages across methods for comparisons that maximize the calibrations and proteins used, indicated in bold. Abbreviations: CD= Chilopoda-Diplopoda calibration (423 Ma); DA= Deuterostomia-Arthropoda calibration (993 Ma); N/A = not applicable; XA= Xiphosura-Arachnida calibration (480 Ma).

Chilopoda-Diplopoda

DA

5

5

433 ± 39

464 ± 68

433 ± 39

468 ± 68

389 ± 59

451 ± 45

381

442 ± 50

XA

5

4

398 ± 79

N/A

357 ± 79

N/A

499 ± 57

474 ± 40

537

XA & DA

5

4

398 ± 38

425 ± 79

376 ± 38

384 ± 79

469 ± 44

469 ± 36

439

XA &/or DA

5

5

430 ± 43

457 ± 69

404 ± 39

426 ± 73

469 ± 44

469 ± 36

439

Xiphosura-Arachnida

DA

5

4

521 ± 71

534 ± 44

511 ± 71

526 ± 44

372 ± 58

448 ± 40

373

475 ± 53

CD

5

4

563 ± 92

N/A

568 ± 92

N/A

403 ± 48

418 ± 36

467

CD & DA

5

4

526 ± 73

534 ± 48

519 ± 73

532 ± 48

394 ± 41

432 ± 35

394

Branchiopoda-Malacostraca

DA

9

3

625 ± 8

551 ± 19

640 ± 8

591 ± 19

670 ± 58

631 ± 37

655

614 ± 23

XA

5

0

N/A

N/A

N/A

N/A

680 ± 87

643 ± 56

806

XA & DA

5

0

N/A

N/A

N/A

N/A

594 ± 50

638 ± 33

595

XA &/or DA

5

3

625 ± 8

551 ± 19

640 ± 8

591 ± 19

632 ± 54

638 ± 33

625

CD

5

0

N/A

N/A

N/A

N/A

581 ± 75

561 ± 51

717

XA & D

5

0

N/A

N/A

N/A

N/A

635 ± 74

608 ± 47

729

CD & DA

5

0

N/A

N/A

N/A

N/A

554 ± 51

616 ± 34

563

Insecta-Crustacea

DA

47

36

765 ± 74

700 ± 72

669 ± 34

643 ± 33

616 ± 53

788 ± 22

577

666 ± 58

XA

5

4

619 ± 132

N/A

534 ± 132

N/A

744 ± 89

802 ± 69

875

XA & DA

5

4

617 ± 92

646 ± 99

562 ± 92

576 ± 99

647 ± 46

763 ± 17

645

XA &/or DA

47

36

741 ± 87

698 ± 70

615 ± 63

609 ± 66

631 ± 49

763 ± 17

611

CD

5

5

650 ± 98

N/A

568 ± 98

N/A

637 ± 77

687 ± 56

779

XA & D

5

4

612 ± 95

N/A

573 ± 93

N/A

695 ± 75

737 ± 48

729

CD & DA

5

5

641 ± 69

665 ± 70

578 ± 69

593 ± 70

605 ± 48

758 ± 18

611

Myriapoda-Chelicerata

DA

6

4

594 ± 51

664 ± 84

630 ± 51

716 ± 84

630 ± 62

664 ± 32

589

642 ± 63

XA

5

2

674 ± 110

N/A

605 ± 110

N/A

751 ± 67

728 ± 49

847

XA & DA

5

2

582 ± 57

668 ± 166

576 ± 57

594 ± 166

675 ± 32

689 ± 26

669

XA &/or DA

6

4

602 ± 51

664 ± 80

603 ± 54

655 ± 125

652 ± 47

689 ± 26

629

CD

5

3

560 ± 18

N/A

544 ± 18

N/A

640 ± 56

647 ± 40

757

XA & D

5

2

594 ± 29

N/A

638 ± 29

N/A

700 ± 47

687 ± 34

772

CD & DA

5

3

608 ± 49

668 ± 83

558 ± 49

576 ± 83

618 ± 34

642 ± 25

621

(Myriapoda-Chelicerata)-Pancrustacea

DA

24

22

747 ± 40

731 ± 41

717 ± 40

692 ± 41

690 ± 61

727 ± 20

602

725 ± 46

XA

5

4

783 ± 139

N/A

703 ± 139

N/A

892 ± 97

812 ± 59

1051

XA & DA

5

4

784 ± 65

826 ± 111

740 ± 65

758 ± 111

768 ± 35

738 ± 19

764

XA &/or DA

24

22

745 ± 41

729 ± 41

728 ± 52

725 ± 76

729 ± 48

738 ± 19

683

CD

5

5

791 ± 79

N/A

727 ± 79

N/A

767 ± 82

734 ± 56

940

XA & D

5

4

747 ± 86

N/A

754 ± 86

N/A

836 ± 77

769 ± 51

956

CD & DA

5

5

784 ± 42

815 ± 66

761 ± 42

780 ± 66

727 ± 38

721 ± 19

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